Download GCSE Workbook 2 816KB - The John Warner School

Forces and Motion
Physics 1 Velocity and Acceleration
●The velocity of an object is its speed in a given direction
●The acceleration of an object is given by the equation:
𝑣−𝑢
𝑎=
𝑡
a is the acceleration in metres per second squared, m/s2.
v is the final velocity in metres per second, m/s.
u is the final velocity in metres per second, m/s.
t is the time taken in seconds, s.
Physics 2 Motion Graphs
●Interpret data from tables and graphs relating to speed, velocity and acceleration.
●The gradient of a distance-time graph represents speed. Candidates should be able to construct distance-time graphs for an
object moving in a straight line when the body is stationary or moving with a constant speed.
●Calculation of the speed of an object from the gradient of a distance-time graph
●The gradient of a velocity-time graph represents acceleration
●Calculation of the acceleration of an object from the gradient of a velocity-time graph
●Calculation of the distance travelled by an object from the area under a velocity-time graph
Physics 3 Resultant Force
●Whenever two objects interact, the forces they exert on each other are equal and opposite.
●A number of forces acting at a point may be replaced by a single force that has the same effect on the motion as the original
forces all acting together. This single force is called the resultant force.
●A resultant force acting on an object may cause a change in its state of rest or motion. Candidates should be able to determine
the resultant of opposite or parallel forces acting in a straight line.
●If the resultant force acting on a stationary object it:
■zero, the object will remain stationary
■non-zero, the object will accelerate in the direction of the resultant force.
●If the resultant force acting in a moving object is:
■zero, the object will continue to move at the same speed and in the same direction.
■not zero, the object will accelerate in the direction of the resultant force.
●The acceleration of an object is determined by the resultant force acting on the object and the mass of the object.
𝐹 =𝑚×𝑎
F is the resultant force in newtons, N.
m is the mass in kilograms, kg.
a is the acceleration in metres per second squared, m/s2.
Physics 4 Terminal Velocity
●Evaluate how the shape and power of a vehicle can be altered to increase the vehicle’s top speed
●Draw and interpret velocity-time graphs for objects that reach terminal velocity, including a consideration of the forces acting on
the object.
●The faster an object moves through a fluid the greater the frictional forces that act on it.
●An object falling through a fluid will initially accelerate due to the force of gravity. Eventually the resultant force will be zero and
the object will move at its terminal velocity (steady speed). Candidates should understand why the use of a parachute reduces the
parachutist’s terminal velocity
●Draw and interpret velocity-time graphs for objects that reach terminal velocity, including a consideration of the forces acting o the
object.
●Calculate the weight of an object using the force exerted on it by a gravitational force.
𝑊 =𝑚×𝑔
W is the weight in newtons, N.
m is the mass in kilograms, kg.
g is the gravitational field strength in newtons per kilogram, N/kg.
Physics 5 Stopping Distance
●Evaluate the effects of alcohol and drugs on stopping distance.
●When a vehicle travels at a steady speed the resistive forces balance the driving force. Candidates should realise that most of the
resistive forces are caused by air resistance.
●The greater the speed of a vehicle the greater the braking force needed to stop it in a certain distance. Candidates should
understand that for a given braking force the greater the speed the greater the stopping distance.
●The stopping distance of a vehicle is the sum of the distance the vehicle travels during the driver’s reaction time (thinking
distance) and the distance it travels under the braking force (braking distance)
●A driver’s reaction time can be affected by tiredness, drugs and alcohol. Candidates should appreciate that distractions may
affect a driver’s ability to react.
●When the brakes of a vehicle are applied, work done by the friction force between the brakes and the wheel reduces the kinetic
energy of the vehicle and the temperature of the brakes increase.
●A vehicle’s braking distance can be affected by adverse road and weather conditions and poor condition of the vehicle.
Candidates should understand that ‘adverse road conditions’ includes wet or icy conditions. Poor condition of the car is limited to
the car’s brakes or tyres.
Physics 6 Hooke’s Law
●A force acting on an object may cause a change in shape of the object
●A force applied to an elastic object such as a spring will result in the object stretching and storing elastic potential energy.
Calculations of the energy stored when stretching an elastic materials is not required.
●For an object that is able to recover its original shape, elastic potential energy is stored in the object when work is done on the
object to change its shape
●The extension of an elastic object is directly proportional to the force applied, provided that the limit of proportionality is not
exceeded:
𝐹 =𝑘×𝑒
F is the force in newtons, N.
k is the spring constant in newtons per metre, N/m.
e is the extension in metres, m.
Physics 1 Velocity and Acceleration
If something is described as ‘fast’ it means that __________________________________________________________________
________________________________________________________________________________________________________
If something is described as ‘slow’ it means that _________________________________________________________________
________________________________________________________________________________________________________
𝑑
𝑣=
𝑡
Symbol
Quantity
Units
Unit Symbol
v
d
t
Rearrange the equation to make d and then t the subject
What is the difference between speed and velocity?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What does the word ‘accelerate’ mean?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
∆𝑣
𝑎=
𝑡
Symbol
Quantity
a
Δv
t
Rearrange the equation to make Δv and then t the subject
Units
Unit Symbol
Physics 2 Motion Graphs
Sketch what the distance-time graph and speed-time graph would look like for:
1 An object moving at a constant speed
2 An object that is speeding up
3 An object that is slowing down
What does the word gradient mean?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Gradients can be calculated using the equation:
𝑔𝑟𝑎𝑑𝑖𝑒𝑛𝑡 =
∆𝑦
∆𝑥
The gradient of a distance-time graph gives us __________________________________________________________________
The gradient of a speed-time graph gives us ____________________________________________________________________
The area under a speed-time graph gives us ____________________________________________________________________
Here are six graphs representing the motion of different objects.
Graph 1
Graph 2
Graph 3
Graph 4
Graph 1
Which sections of the graph show that the object is…
Stationary?
_________________________________________________________________________
Moving at a constant speed?
_________________________________________________________________________
Moving with increasing speed?
_________________________________________________________________________
Moving with decreasing speed?
_________________________________________________________________________
Moving with the greatest speed?
_________________________________________________________________________
Calculate the gradient of the line AB
____________________________________________
Calculate the gradient of the line CD
____________________________________________
Calculate the gradient of the line DE
____________________________________________
Graph 2
Which sections of the graph show that the object is…
Stationary?
_________________________________________________________________________
Moving at a constant speed?
_________________________________________________________________________
Moving with increasing speed?
_________________________________________________________________________
Moving with decreasing speed?
_________________________________________________________________________
Moving with the greatest speed?
_________________________________________________________________________
Calculate the gradient of the line 0A
____________________________________________
Calculate the gradient of the line AB
____________________________________________
Calculate the gradient of the line CD
____________________________________________
Calculate the gradient of the line DE
____________________________________________
Graph 3
Which sections of the graph show that the object is…
Stationary?
_________________________________________________________________________
Moving at a constant speed?
_________________________________________________________________________
Moving with increasing speed?
_________________________________________________________________________
Moving with decreasing speed?
_________________________________________________________________________
Calculate the gradient of BC
____________________________________________
Calculate the area under the graph
____________________________________________
Graph 4
Which sections of the graph show that the object is…
Stationary?
_________________________________________________________________________
Moving at a constant speed?
_________________________________________________________________________
Moving with increasing speed?
_________________________________________________________________________
Moving with decreasing speed?
_________________________________________________________________________
Calculate the gradient of line W
____________________________________________
Calculate the gradient of line X
____________________________________________
Calculate the gradient of line Z
____________________________________________
Calculate the area under Y
____________________________________________
Physics 3 Resultant Force
If two forces are described as balanced what does this mean? ______________________________________________________
________________________________________________________________________________________________________
If two forces are described as unbalanced what does this mean? ____________________________________________________
________________________________________________________________________________________________________
What does the term ‘resultant force’ mean? _____________________________________________________________________
________________________________________________________________________________________________________
𝐹 =𝑚×𝑎
Symbol
Quantity
Units
Unit Symbol
F
m
a
Rearrange the equation to make m and then a the subject
For each of the following situations calculate the resultant force and describe what would happen to the object:
A) The object is initially stationary
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
B) The object is initially stationary
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
C) The object is initially stationary
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
D) The object is initially moving to the right
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
E) The object is initially moving to the right
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
F) The object is initially moving to the right
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
G) The object is initially moving to the left
Resultant Force: Size _____________________
Direction ___________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 4 Terminal Velocity
As an object speeds up the air resistance will __________________________________________________________
𝑊 =𝑚×𝑔
Symbol
Quantity
Units
Unit Symbol
W
m
g
Rearrange the equation to make m and then g the subject
Below are stages of a parachutist as they travel from plane to ground. For each stage describe how the weight and air resitance
compare to each other.
A) A parachutist as they stand in the plane, ready to jump
________________________________________________________________________________________________________
B) Immediately after they have left the plane
________________________________________________________________________________________________________
C) 20 seconds after they have left the plane and are falling through the air
________________________________________________________________________________________________________
D) When the parachutist stops accelerating and travels at a constant speed
________________________________________________________________________________________________________
E) When the parachute first opens
________________________________________________________________________________________________________
F) When the parachutist reaches terminal velocity again
________________________________________________________________________________________________________
G) When the parachutist is stood on the ground.
________________________________________________________________________________________________________
Sketch a velocity-time graph for the parachute jump. Add labels for the stages A to G.
Physics 5 Stopping Distances
When the brakes of a vehicle are applied and it comes to rest where does the energy go and what effect does it have?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
The overall stopping distance of a vehicle is given by the equation:
𝑠𝑡𝑜𝑝𝑝𝑖𝑛𝑔 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 = 𝑡ℎ𝑖𝑛𝑘𝑖𝑛𝑔 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒 + 𝑏𝑟𝑎𝑘𝑖𝑛𝑔 𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒
Explain what is meant by thinking distance
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Explain what is meant by braking distance
________________________________________________________________________________________________________
________________________________________________________________________________________________________
If the driver’s reaction time was reduced what effect would this have on the stopping distance?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
List the factors that can affect the thinking distance and for each one explain how it affects it (e.g. increases distance).
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
List the factors that can affect the braking distance and for each one explain how it affects it (e.g. increases distance).
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What can affect both the thinking and braking distance?
________________________________________________________________________________________________________
Physics 6 Hooke’s Law
When a force acts on a spring (because a mass is hung on it) it will stretch. Which type of energy will it now have?
________________________________________________________________________________________________________
The extension is directly proportional to the force applied. What does directly proportional mean?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
How could you tell that an object follows Hooke’s law from a graph of force (y axis) against extension (x axis)?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What would the graph look like if you replaced the original spring with a spring of larger spring constant?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
How can you find the spring constant from the graph?
________________________________________________________________________________________________________
What is the point called when the force and extension are no longer directly proportional?
________________________________________________________________________________________________________
Describe the energy changes that happen as a bungee jumper travels from their highest to lowest point.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Why doesn’t the bungee jumper reach the same higher as they jumped from?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
𝐹 =𝑘×𝑒
Symbol
Quantity
F
k
e
Rearrange the equation to make k and then e the subject
Units
Unit Symbol
Energy and Momentum
Physics 7 Work Done and Power
●When a force causes an object to move through a distance work is done.
●Work done, force and distance moved are related by the equation:
𝑊 =𝐹×𝑑
W is the work done in joules, J.
F is the force applied in newtons, N.
d is the distance moved in the direction of the force in metres, m.
●Energy is transferred when work is done. Candidates should be able to discuss the transfer of kinetic energy in particular
situations. Examples might include shuttle re-entry or meteorites burning up in the atmosphere.
●Work done against frictional forces.
●Power is the work done or energy transformed in a given time:
𝐸
𝑃=
𝑡
P is the power in watts, W.
E is the energy transferred in joules, J.
t is the time taken in seconds, s.
Physics 8 Kinetic and Potential Energy
●Gravitational potential energy is the energy that an object has by virtue of its position in a gravitational field.
𝐸𝑃 = 𝑚 × 𝑔 × ℎ
Ep is the change in gravitational potential energy in joules, J.
m is the mass in kilograms, kg.
g is the gravitational field strength in newtons per kilogram, N/kg.
h is the change in height in metres, m.
Candidates should understand that when an object is raised vertically work is done against gravitational force and the object gains
gravitational potential energy.
●The kinetic energy of an object depends on its mass and its speed
1
𝐸𝐾 = × 𝑚 × 𝑣 2
2
EK is the kinetic energy in joules, J.
m is the mass in kilograms, kg.
v is the speed in metres per second, m/s.
Physics 9 Momentum
●Momentum is a property of moving objects:
𝑝 =𝑚×𝑣
p is the momentum in kilograms metres per second, kg m/s.
m is the mass in kilograms, kg.
v is the velocity in metres per second, m/s.
Physics 10 Collisions and Explosions
●In a closed system the total momentum before an event is equal to the total momentum after the event. This is called the
conservation of momentum. Candidates may be required to complete calculation involving two objects. Examples of events are
collisions and explosions.
Physics 11 Car Safety Features
●Evaluate the benefits of air bags, crumple zones, seat belts and side impact bars in cars. This should include ideas of both
energy changes and momentum changes
●Evaluate the benefits of different types of braking systems, such as regenerative braking
Physics 7 Work Done and Power
Work is done when a force causes an object to __________________________________________________________________
What affects the energy that I use whilst moving a trolley across a floor?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
When work done is ______________________________________________________________________________
𝑊 =𝐹×𝑑
Symbol
Quantity
Units
Unit Symbol
W
F
d
Rearrange the equation to make F and then d the subject.
When a force causes an object to move across the floor what is work done against?
_________________________________
What are the energy transformations as this happens?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
When a force causes an object to move up through the air what is work done against?
_________________________________
What are the energy transformations as this happens?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Calculate the work done when a force of 4 N moves a chair by 5.7 m across the ground.
How high could 90 J raise a box of weight 1.2 kN?
𝐸
𝑃=
𝑡
Symbol
Quantity
Units
Unit Symbol
P
E
t
Rearrange the equation to make E and then t the subject.
Which of these speakers is the most powerful? Speaker A transfers 3510000 J in 24 hours and speaker B transfers 3.8 kJ in 1
minute 34 seconds?
Physics 8 Kinetic and Potential Energy
What is gravitational potential energy?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
𝐸𝑃 = 𝑚 × 𝑔 × ℎ
Symbol
Quantity
EP
m
g
h
Rearrange the equation to make m and then h the subject.
Units
Unit Symbol
What is kinetic energy?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
1
𝐸 = 2 × 𝑚 × 𝑣2
Symbol
Quantity
Units
Unit Symbol
EK
m
v
Rearrange the equation to make m and then v the subject.
Ford Fiesta
1465 kg
Vauxhall Astra
1685 kg
Smart City Coupe
730 kg
Ferrari 360 Spider
1350 kg
Ford Transit Van
1850 kg
Pick two cars from the choice above and calculate the kinetic energy it would have travelling at 14 m/s (around 30 miles per hour).
Now calculate the change in gravitational potential energy when they roll down a hill of height 5 m.
A 70 kg woman sits at the top of a slide 4 m above the ground. Calculate the speed that she will be travelling at when she reaches
the bottom of the slide.
She is actually travelling slower than this speed, explain why.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
A man is driving a car with a total mass of 1450 kg at 15 m/s along a flat section of road at the bottom of a hill. If the man turns off
the engine at the bottom of the hill what height will he get to?
The car does actually get that high up the hill, explain why.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 9 Momentum
What is the difference between speed and velocity?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
𝑝=𝑚×𝑣
Symbol
Quantity
p
m
v
Rearrange the equation to make m and then v the subject.
Units
Unit Symbol
How can an object travelling at a constant speed have a changing momentum?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 10 Collisions and Explosions
What does the conservation of momentum mean?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
The diagram shows a car and a van, just before and just after the car collided with the van.
Before the collision
After the collision
What is the momentum of the car before the collision?
________________________________________________________________________________________________________
What is the momentum of the van before the collision?
________________________________________________________________________________________________________
What is the total momentum before the collision?
________________________________________________________________________________________________________
What is the total momentum after the collision?
________________________________________________________________________________________________________
What is the momentum of the car after the collision?
________________________________________________________________________________________________________
What is the momentum of the van after the collision?
________________________________________________________________________________________________________
What is the velocity of the van after the collision?
________________________________________________________________________________________________________
What assumption have you made during these calculations?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
The picture shows two teenagers riding identical skateboards. The skateboards are moving at the same speed and the teenagers
have the same mass.
Why don’t the teenagers have the same momentum?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
One of the skateboarders slows down and stops. The teenager then jumps off the
skateboard, causing it to recoil and move in the opposite direction
The teenager, of mass 55 kg, jumps off the skateboard at 0.4 m/s causing the skateboard
to recoil at 10 m/s.
What is the total momentum before the jump? ____________________________
What is the total momentum after the jump? ____________________________
What is the momentum of the teenager?
________________________________________________________________________________
What is the momentum of the skateboard?
________________________________________________________________________________________________________
What is the mass of the skateboard?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 11 Car Safety Features
How do the side impact bars of a vehicle protect passengers?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Air bags, crumple zones and seat belts all keep passengers safe by the same basic principle; they reduce the force the passengers
experience by ___________________________________________________________________________________________
for the momentum of the vehicle and passengers to _____________________________________________________________
The front crumple zone of a car is tested at a road traffic laboratory. This is done by using a remote control device to drive the car
into a strong barrier. Electronic sensors are attached to the dummy inside the car.
Describe the energy changes that occur as the vehicle comes to rest. Mention the types of energy and where it is transferred to.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What does the crumple zone do?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What do seat belts do and what could happen during a crash if seatbelts weren’t used?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What do air bags do and what could happen during a crash if there weren’t any air bags?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Hybrid cars have an electric engine and a petrol engine. This type of car is often fitted with a regenerative braking system. A
regenerative braking system not only slows a car down but at the same time causes a generator to charge the car’s battery.
State and explain the benefit of a hybrid car being fitted with a regenerative braking system.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Electrical Circuits
Physics 12 Static Electricity
●When certain insulating materials are rubbed against each other they become electrically charged. Negatively charged electrons
are rubbed off one material and onto each other.
●The material that gains electrons becomes negatively charged. The material that loses electrons is left with an equal positive
charge.
●When two electrically charged objects are brought together they exert a force on each other.
●Two objects that carry the same type of charge repel. Two objects that carry different types of charge attract.
●Electrical charges can move easily through some substance, eg metals
Physics 13 Circuits
●Electrical current is a flow of electric charge. The size of the electric current is the rate of flow of electric charge. The size of the
current is given by the equation:
𝑄
𝐼=
𝑡
I is the current in amperes (amps), A.
Q is the charge in coulombs, C.
t is the time in seconds, s.
●The potential difference (voltage) between two points in an electric circuit is the work done (energy transferred) per coulomb of
charge that passes between the points.
𝑊
𝑉=
𝑄
V is the potential difference in volts, V.
W is the work done in joules, J.
Q is the charge in coulombs, C.
Teachers can use either of the terms potential difference or voltage. Questions will be set using the term potential difference.
Candidates will gain credit for the correct use of either term.
●The resistance of a component can be found by measuring the current through, and potential difference across, the component.
●The current through a resistor (at a constant temperature) is directly proportional to the potential difference across the resistor.
●Calculate current, potential difference or resistance using the equation:
𝑉 =𝐼×𝑅
V is the potential difference in volts, V.
I is the current in amperes (amps), A.
R is the resistance in ohms, Ω.
●The current through a component depends in its resistance. The greater the resistance the smaller the current for a given
potential difference across the component.
Physics 14 Components
●Apply the principles of basic electrical circuits to practical situations
●Circuit diagrams using standard symbols. The following standard symbols should be known:
Switch (open)
Switch (closed)
Lamp
Fuse
Cell
Battery
Voltmeter
Ammeter
Resistor
Variable resistor
Thermistor
Diode
LED
LDR
Candidates will be required to interpret and draw circuit diagrams. Knowledge and understanding of the uses of thermistors in
circuits, eg thermostats is required. Knowledge and understanding of the applications if light-dependent resistors (LDRs) is
required, eg switching lights on when it gets dark.
●The resistance of a light-dependent resistor (LDR) decreases as light intensity increases.
●The resistance of a thermistor decreases as the temperature increases. Knowledge of a negative temperature coefficient
thermistor only is required.
Physics 15 I-V Graphs
● Evaluate the use of different forms of lighting, in terms of cost and energy efficiency. Examples might include filament bulbs,
fluorescent bulbs and light-emitting diodes (LEDs).
●Current-potential difference graphs are used to show how the current through a component varies with the potential difference
across it.
●The current-potential difference graphs for a resistor at constant temperature.
●The resistance of a filament bulb increases as the temperature of the filament increases.Candidates should be able to explain
resistance change in terms of ions and electrons.
●The current through a diode flows in one direction only. The diode has a very high resistance in the reverse direction.
Resistor
Filament Lamp
Diode
●An LED emits light when a current flows through it in the forward direction.
Candidates should be aware that there is an increasing use of LEDs for lighting, as they use a much smaller current than other
forms of lighting.
Physics 16 Series and Parallel Circuits
●The potential difference provided by cells connected in series is the sum of the potential difference of each cell (depending on the
direction in which they are connected).
●For components connected in series:
■ the total resistance is the sum of the resistance of each components
■ there is the same current through each component
■ the total potential difference across each component is the same
●For components connect in parallel
■ the potential difference across each component is the same
■ the total current through the whole circuit is the sum of the currents through the separate components.
Physics 12 Static Electricity
This is a diagram of an atom, it has the same number of positive ______________________ in
the nucleus as it has negative _____________________ orbiting the nucleus.
The nucleus is strongly bonded together so particles inside it almost never get out.
Explain what an ion is.
________________________________________________________________________________________________________
Explain how the following ions are formed from the atom above. Include a diagram like the one above to help with your explanation.
A positive 1+ ion
A negative 1– ion
A positive 2+ ion
A negative 2– ion
An electrical conductor is a material that _______________________________________________________________________
An electrical insulator is a material that _________________________________________________________________________
When two insulating objects are rubbed together the force of ____________________________ can knock electrons off of one
material and on to another.
The material that gains electrons has becomes __________________________________________________________________
The material that has lost electrons has becomes ________________________________________________________________
Two materials that have the same charge will ___________________________________
Two materials that have opposite charges will ___________________________________
Static is different to current because ___________________________________________________________________________
________________________________________________________________________________________________________
Static will only build up on ___________________________________________________
This is because ___________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 13 Circuits
Explain what the following words mean:
Voltage__________________________________________________________________________________________________
________________________________________________________________________________________________________
Another term for voltage is ________________________________________________________
Current__________________________________________________________________________________________________
________________________________________________________________________________________________________
Resistance_______________________________________________________________________________________________
________________________________________________________________________________________________________
The current through a resistor (at a constant temperature) is directly proportional to the potential difference across the resistor.
What does directly proportional mean?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What would happen if...
1) The resistance was kept the same but the voltage was increased?
________________________________________________________________________________________________________
2) The resistance was kept the same but the voltage was reversed?
________________________________________________________________________________________________________
3) The resistance was increased but the voltage was kept the same?
________________________________________________________________________________________________________
4) A wire is heated to a higher temperature? (What does this do to the resistance?)
________________________________________________________________________________________________________
To take readings of voltage and current you must make sure that the meters are
connected properly. Complete the diagram to the right.
You must connect a voltmeter in
_____________________________
You must connect an ammeter in
_____________________________
Why does the bulb light up when it is connected to the battery?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
𝑉 =𝐼×𝑅
Symbol
Quantity
Units
Unit Symbol
Units
Unit Symbol
Units
Unit Symbol
V
I
R
Rearrange the equation to make Q and then t the subject
𝑄
𝐼=
𝑡
Symbol
Quantity
I
Q
t
Rearrange the equation to make Q and then t the subject
𝑊
𝑉=
𝑄
Symbol
Quantity
V
W
Q
Rearrange the equation to make W and then Q the subject
Physics 14 Components
Name
Symbol
Description of what is does
Cell
Battery
Switch
Lamp
Voltmeter
Ammeter
Resistor
Variable
Resistor
LDR
Thermistor
Diode
Fuse
Complete this graph to show how the resistance of an LDR
changes when the light levels are increased.
Complete this graph to show how the resistance of a thermistor
changes when it is warmed up.
Physics 15 I-V Graphs
Component: __________________________
As the voltage increases the current increases.
When the voltage is increased the current goes up by the
same amount.
When you reverse the voltage (negative) you reverse the
current.
Component: __________________________
As the voltage increases the current increases.
When the voltage is increased the current doesn’t always go
up by the same amount.
When you reverse the voltage (negative) no current flows.
Component: __________________________
As the voltage increases the current increases.
When the voltage is increased the current goes up by the
same amount until the lamp gets hot and the resistance
changes. At this point when the voltage in increased the
current doesn’t increase by the same amount.
When you reverse the voltage (negative) you reverse the
current.
Getting the Results
You can get the results for the above by using the circuit
drawn to the right.
Voltmeters are attached in ________________
They measure the ________________________
Ammeters are attached in ________________
They measure the ________________________
The variable resistor is used to ______________
________________________________________
There is an increase in the use of LEDs for lighting instead of filament lamps. Outline the advantages of using LEDs instead of
traditional light bulbs.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 16 Series and Parallel Circuits
If components are set up in ‘series’ what does this mean?__________________________________________________________
________________________________________________________________________________________________________
If components are set up in ‘parallel’ what does this mean?_________________________________________________________
________________________________________________________________________________________________________
Series Circuits
The current leaving the cell will _______________________________________________________________________________
ICell
I1
I2
The voltage of the cell will ___________________________________________________________________________________
VCell
V1
V2
If we wanted to replace resistor 1 and 2 with a single resistor we can work out the total resistor of resistors in series using the equation:
RTotal
R1
R2
Parallel Circuits
The current leaving the cell will _______________________________________________________________________________
ICell
I3
I4
The voltage of the cell will ___________________________________________________________________________________
VCell
V3
V4
Mains Electricity
Physics 17 AC and DC
●Cells and batteries supply a current that always passes in the same direction. This is called direct current (d.c.).
●An alternating current (a.c.) is one that is constantly changing direction.
Candidates should be able to compare and calculate potential differences of d.c. supplies and the peak potential difference of a.c.
supplies from diagrams of oscilloscope traces.
Candidates should be able to determine the period and hence the frequency of a supply from diagrams of oscilloscope traces.
●Mains electricity is an a.c. supply. In the UK it has a frequency of 50 cycles per second (50 Hertz) and is about 230V.
Physics 18 3 Pin Plugs and Circuit Breakers
●Understand the principles of safe practice and recognise dangerous practice in the use of mains electricity.
●Compare the uses of fuses and circuit breakers
●Evaluate and explain the need to use different cables for different appliances
●Most electrical appliances are connected to the mains using cable and a three-pin plug.
●The structure of electrical cable. Candidates should be familiar with both two-core and three-core cable.
●The structure and wiring of a three-pin plug. Knowledge and understanding of the materials used in three-pin plugs is required, as
is the colour coding of the covering of the three wires.
●If an electrical fault causes too great a current, the circuit is disconnected by a fuse or a circuit breaker in the live wire.
●When the current in a fuse wire exceeds the rating of the fuse it will melt, breaking the circuit.
●Some circuits are protected by Residual Current Circuit Breakers (RCCBs).
Candidates should realise that RCCBs operate by detecting a difference in the current between the live and neutral wires.
Knowledge of how the devices do this is not required. Candidates should be aware of the fact that this device operates much
faster than a fuse.
●Appliances with metal cases are usually earthed. Candidates should be aware that some appliances are double insulated, and
therefore have no earth wire connection.
●The earth wire and fuse together protect the wiring of the circuit. Candidates should have an understanding of the link between
cable thickness and fuse values.
Physics 19 Electrical Power
●Consider the factors involved when making a choice of electrical appliances. Candidates should consider the efficiency and
power of the appliances.
●When an electrical charge flows through a resistor the resistor gets hot. Candidates should understand that a lot of energy is
wasted in filament bulbs by heating. Less energy is wasted in power saving lamps such as Compact Fluorescent Lamps
(CFLs).Candidates should understanding that there is a choice when buying new applications in how efficiently they transfer
energy.
●The rate at which energy is transferred by an appliance is called the power.
𝐸
𝑃=
𝑡
P is power in watts, W,
E is energy in joules, J,
t is time in seconds, s
●Power, potential difference and current are related by the equation:
𝑃 =𝐼×𝑉
P is power in watts, W.
I is current in amperes (amps), A.
V is potential difference in volts, V
Candidates should be able to calculate the current through an appliance from its power and the potential difference of the supply,
and from this determine the size of fuse needed.
●Energy transferred, potential difference and charge are related by the equation:
𝐸 =𝑉×𝑄
E is energy in joules, J.
V is potential difference in volts, V.
Q is charge in coulombs, C.
Physics 17 AC and DC
What is meant by direct current?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Name the sources of direct current ____________________________________________________________________________
What is meant by alternating current?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
We call the electricity from the plug sockets the ‘Mains’ supply.
What is the frequency of the UK Mains supply?
Value: _______________ units: ______________
What is the voltage/potential difference of the UK Mains supply?
Value: _______________ units: ______________
An oscilloscope is a device used to measure and show the size of voltages or currents and how they change over time.
Sketch the oscilloscope traces (graphs) for the following electrical supplies.
A DC supply
A smaller DC supply
that has been reversed
An AC supply
An AC supply with a
smaller voltage
An AC supply with a
lower frequency
What is the time period of an alternating supply and how can you measure it on an oscilloscope trace?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
1
𝑓=
𝑇
Symbol
Quantity
Units
Unit Symbol
f
T
Physics 18 3 Pin Plugs and Circuit Breakers
What material is the case of a plug made from? _________________________________
Why? ___________________________________________________________________________________________________
What material are the inner wires of a plug made from? _________________________________
Why? ___________________________________________________________________________________________________
What material are the pins made from? _________________________________
Why? ___________________________________________________________________________________________________
When electricity gets to our homes we use plugs with three pins to connect it to the appliances we want to use. Name the parts of
the plug from the diagram below; include the colours of the wires.
wire X
A
3A
B
Wire X
Wire Y
Wire Z
A
wire Z
wire Y
B
Typical household fuses come in 3, 5 and 13 A; it is important to choose the most appropriate fuse for the appliance.
Describe what would happen if a fuse was used with a rating below the expected current of the appliance.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Explain why it is important not to choose a fuse rating a lot higher than the expected current that the appliance will use.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is the link between cable thickness and the maximum current than can flow safely?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is the earth wire for? How do the earth wire and fuse help keep us and the wiring safe?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Some appliances don’t need an earth wire, why not?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Circuit breakers can also be used instead of a fuse. What are the advantages of using a circuit breaker to do the same job?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Residual Current Circuit Breakers (RCCBs) operate by detecting a difference in the current between the ___________________
and ___________________ wires. What are the advantages of using a RCCB over a normal circuit breaker?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 19 Electrical Power
𝐸
𝑃=
𝑡
Symbol
Quantity
Units
Unit Symbol
Units
Unit Symbol
Units
Unit Symbol
P
E
t
Rearrange the equation to make E and then t the subject
𝑃 =𝐼×𝑉
Symbol
Quantity
P
I
V
Rearrange the equation to make I and then V the subject
𝐸 =𝑉×𝑄
Symbol
Quantity
E
V
Q
Rearrange the equation to make V and then Q the subject
Atoms and Radiation
Physics 20 Rutherford and Atoms
●Explain how results from Rutherford and Marsden scattering experiments led to the ‘plum pudding’ model being replaced by the
nuclear model. Candidates should realise that new evidence can cause a theory to be re-evaluated.Candidates should realise that,
according to the nuclear model, most of the atom is empty space.
●The basic structure of an atom is a small central nucleus composed of protons and neutrons surrounded by electrons.
Candidates should appreciate the relative size of the nucleus compared to the size of the atom.
●The relative masses and relative charges of protons, neutrons and electrons.
●In an atom the number of electrons is equal to the number of protons in the nucleus. The atom has no overall electrical charge.
Physics 21 Ions and Isotopes
●Atoms may lose or gain electrons to form charged particles called ions.
●The atoms of an element always have the same number of protons, but have a different number of neutrons for each isotope.
The total number of protons in an atom is called its atomic number. The total number of protons and neutrons in an atom is called
its mass number.
Physics 22 Alpha, Beta and Gamma
●Some substances give out radiation from the nuclei of their atoms all the time, whatever is done to them. These substances are
said to by radioactive. Candidates should be aware of the random nature of radioactive decay.
●Identification of an alpha particle as two protons and two neutrons, the same as a helium nucleus, a beta particle as an electron
from the nucleus and gamma radiation as electromagnetic radiation.
Physics 23 Properties and Uses
●Evaluate the possible hazards associated with the use of different types of nuclear radiation
●Evaluate measures that can be taken to reduce exposure to nuclear radiations
●Properties of the alpha, beta and gamma radiations limited to their relative ionising power, their penetration through materials and
their range in air.
●Alpha and beta radiations are deflected by both electric and magnetic fields but gamma radiation is not.All candidates should
know that alpha particles are deflected less than beta particles and in an opposite direction.Higher tier candidates should be able to
explain this in terms of the relative mass and charge of each particle.
●The uses of and the dangers associated with each type of nuclear radiation.
Physics 24 Half-Life
●Evaluate the appropriateness of radioactive sources for particular uses, including as tracers, in terms of the type(s) of radiation
emitted and their half-lives.
●The half-life of a radioactive isotope is the average time it takes for the number of nuclei of the isotope in a sample to halve, of the
time it takes for the count rate from a sample containing the isotope to fall to half its initial level.
Physics 25 Background Radiation
●Evaluate the effect of occupation and / or location on the level of background radiation and radiation dose.
●Nuclear equations to show single alpha and beta decay.
Candidates will be required to balance such equations, limited to the completion of atomic number and mass number. The
identification of daughter elements from such decays is not required.
●The origins of background radiation. Knowledge and understanding should include both natural sources, such as rocks and
cosmic rays from space, and man-made sources such as the fallout from nuclear weapons tests and nuclear accidents.
Physics 20 Rutherford and Atoms
There are several models of the atom.
The Solid Sphere Model
The Plum Pudding Model
The Nuclear Model
The Solid Sphere model assumed that the atom was a solid ball like a snooker or golf ball.
The Plum Pudding model describes the atoms as a positive ‘dough’ with negative charges scattered through it at random.
Describe and draw the nuclear model of the atom.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Complete the table below.
Particle
Relative
Charge
Relative
Mass
Where is it found?
Proton
Neutron
Electron
The periodic table displays all the different types of atoms/elements that exist. The boxes on the table look like the ones below:
Explain what the notation in the box tells us (not these specific examples):
1: ____________________________________________
2: ____________________________________________
3: ____________________________________________
4: ____________________________________________
1
2
3
4
9
32
40
80
Be P Ca Br
Beryllium
4
Phosphorus
15
Calcium
20
Bromine
35
How do you work out the number of neutrons that are in an atom?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
An atom is neutral because it has the same number of positive ___________________ as it has negative ___________________
How do you work out the number of electrons that are in an atom?
________________________________________________________________________________________________________
Use the periodic table to help you complete the table below
Number
Name
Symbol
Protons
1
Hydrogen
2
Helium
3
Lithium
4
Be
5
B
6
C
7
Electrons
Atomic Number
Nitrogen
8
9
Neutrons
O
Fluorine
10
Ne
Here is a diagram of the experimental set up that Rutherford used to find out what atoms are like.
Describe what he did:
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
Complete this table on Rutherford’s results and the conclusions that he made:
Observation
The alpha particles where deflected by
something.
The positive alpha particles where
deflected by something.
Only 1 in about every 8000 was
deflected back.
Conclusion
Mass Number
Physics 21 Ions and Isotopes
This is a diagram of an atom, it has the same number of positive ______________________ in
the nucleus as it has negative _____________________ orbiting the nucleus.
The nucleus is strongly bonded together so particles inside it almost never get out.
Explain what an ion is
________________________________________________________________________________________________________
Explain how the following ions are formed from the atom above. Include a diagram like the one above to help with your explanation.
A positive 1+ ion
A negative 1– ion
A positive 2+ ion
A negative 2– ion
Isotopes are different versions of the same element. They all have the same number of ________________________ but a
different number of _____________________
Calculate the number of protons, neutrons and electrons of these isotopes
Isotope
233
92𝑈
235
92𝑈
238
92𝑈
12
6𝐶
13
6𝐶
14
6𝐶
35
17𝐶𝑙
37
17𝐶𝑙
54
26𝐹𝑒
56
26𝐹𝑒
197
79𝐴𝑢
195
79𝐴𝑢
Protons
Neutrons
Electrons
Isotope
Protons
Neutrons
Electrons
Physics 22 Alpha, Beta and Gamma
Explain what the following words mean.
Radioactive ______________________________________________________________________________________________
Decay___________________________________________________________________________________________________
Radiation ________________________________________________________________________________________________
Stable___________________________________________________________________________________________________
The real life scenarios below are like radioactivity. Read them through and fill in the table
Harry is up a ladder painting a wall green. He is holding
Sally has eaten something undercooked and is feeling
onto the ladder with one hand and five cans of paint
What
unwell. She goes to the toilet and is sick. When she
and a brush in the other. The ladder is very wobbly. He
represents…
comes out she is feeling much better.
decides to drop four of the cans so he can hold onto
the ladder better.
Radioactive?
Decay?
Radiation?
Stable?
Complete these tables about the different types of radiation.
Type of
What is it? What is it made from?
Radiation
Diagram
Alpha
Beta
Gamma
Physics 23 Properties and Uses
Type of
Radiation
Alpha
Beta
Gamma
Relative
Charge
Relative
Mass
Ionising
Power
Deflected by
EM Field?
What is it stopped by?
Draw lines to show which source should be stored in each box so that the risk of radiation leakage is a minimum
Aluminium
5 mm thick
Cardboard
2 mm thick
Lead
10 mm thick



Gamma source
Beta source
Alpha source
A radioactive source emits alpha, beta and gamma radiation. The diagram shows what happens to the radiation as it passes
Diagram 1
between two charged plates.
Negatively charged
plate
P
Radioactive
source
Q
R
Positively charged
plate
Identify which types of radiation P, Q and R are.
P
Q
R
How do you know?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Describe and explain the possible dangers from having the following types of radiation OUTSIDE our bodies.
Alpha ___________________________________________________________________________________________________
________________________________________________________________________________________________________
Beta ____________________________________________________________________________________________________
________________________________________________________________________________________________________
Gamma _________________________________________________________________________________________________
________________________________________________________________________________________________________
Describe and explain the possible dangers from having the following types of radiation INSIDE our bodies.
Alpha ___________________________________________________________________________________________________
________________________________________________________________________________________________________
Beta ____________________________________________________________________________________________________
________________________________________________________________________________________________________
Gamma _________________________________________________________________________________________________
________________________________________________________________________________________________________
Radiation is used to control the thickness of paper, cardboard and aluminium when it is manufactured.
Use the diagram to explain how radiation is used in this situation.
________________________________________________
________________________________________________
________________________________________________
________________________________________________
________________________________________________
________________________________________________
________________________________________________
How else could you do this job?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Outline the benefits of using radiation to do this job
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Outline the drawbacks of radiation doing this job
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Radiation is also used in smoke detectors.
Radiation passes between a source and a detector. If particles of smoke
drift between the source and the detector the radiation is absorbed. The
detector then triggers an alarm to alert us.
Outline the benefits of using radiation to do this job
___________________________________________________________
___________________________________________________________
___________________________________________________________
___________________________________________________________
Outline the drawbacks of radiation doing this job
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Radiation is used to sterilise medical equipment like in the diagram. The radiation kills bacteria and viruses on the equipment.
Outline the benefits of using radiation to do this job
_________________________________________________
_________________________________________________
_________________________________________________
_________________________________________________
_________________________________________________
_________________________________________________
Outline the drawbacks of radiation doing this job
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
How else could you do this job?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Radiation can be used as a tracer in medical situations. Briefly explain what this involves.
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
How else could you do this job?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Outline the benefits of using radiation to do this job
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Outline the drawbacks of radiation doing this job
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 24 Half Life
Different radioactive isotopes have different half-lives.
If a radioactive isotope has a long half-life it means that ___________________________________________________________
________________________________________________________________________________________________________
If a radioactive isotope has a short half-life it means that ___________________________________________________________
________________________________________________________________________________________________________
Write an explanation of what half-life is.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Here is experimental data obtained from other radioactive isotopes. Use the skills you have learnt to find the half lives of the
following radioactive isotopes. It is expected that you take more than one measurement and that an average is calculated.
Americium 241
10 000
9000
8000
7000
6000
Number of
americium 5000
atoms
4000
3000
2000
1000
0
0
100
200
300
400 500 600
Time in years
700
800
900 1000
Technetium 99
300
200
Count rate
in counts
per minute
100
0
0
2
4
6
10
15
Phosphorous 32
8
10
12
Time in hours
14
16
18
35
40
45
350
300
250
Count
200
rate in
counts per
minute 150
100
50
0
0
5
20
25
Time in days
30
Isotope
241
95𝐴𝑚
99
43𝑇𝑐
32
15𝑃
Protons
Neutrons
Electrons
What is the half-life of Americium 241? You can draw on the graphs and write your calculations here.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is the half-life of Technetium 99?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is the half-life of Phosphorous 32
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Here is information about some different radioactive isotopes, the radiation they emit and their half-lives.
Isotope
bismuth 83
caesium 135
cobalt 60
hydrogen-3
iridium-192
Radiation emitted
beta
beta
gamma
beta
gamma
Half-life
61 minutes
3 million years
5 years
12 years
74 days
Isotope
polonium 210
polonium-213
radon 222
technetium 99
uranium-239
Radiation emitted
alpha
alpha
alpha
gamma
beta
Half-life
138 days
0.3 seconds
28 years
6 hours
24 minutes
Which isotope would be best suited for controlling the thickness of paper? _____________________________________________
Which isotope would be best suited for sterilising medical equipment? ________________________________________________
Which isotope would be best suited for a household smoke detector? ________________________________________________
Which isotope would be best suited to be injected as a medical tracer? _______________________________________________
Choose one of your answers and justify why the isotope you have chosen is the most suitable.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 25 Background Radiation
We are exposed to a background level of radiation and have been all of our lives.
Complete the pie chart to show the main contributors to
background radiation.
Which are the natural contributors to background radiation levels?
_____________________________________________________
_____________________________________________________
_____________________________________________________
Which are the manmade contributors to background radiation?
_____________________________________________________
_____________________________________________________
_____________________________________________________
What was the count rate of the background radiation in the classroom?
_____________________________________________________
When something undergoes alpha decay it decays by giving out an alpha particle.
This can be presented with the following nuclear equation:
𝐴
𝑍𝑋
→
𝑌 + 42𝛼
Complete this equation
When something undergoes beta decay it decays by giving out a beta particle. A neutron in the nucleus changes into a proton and
an electron. The electron is given out as radiation and the neutron stays in the nucleus.
This can be presented with the following nuclear equation:
𝐴
𝑍𝑋
→
𝑌 + −10𝛽
Complete this equation
Nuclear and Stars
Physics 26 Nuclear Fission
●There are two fissionable substances in common use in nuclear reactors: uranium 235 and plutonium 239. The majority use
uranium 235.
●Nuclear fission is the splitting of an atomic nucleus.
●For fission to occur the uranium 235 or plutonium 239 nucleus must first absorb a neutron.
●The nucleus undergoing fission splits into two smaller nuclei and two or three neutrons and energy is released.
●The neutrons may go on to start a chain reaction. Candidates should be able to sketch or complete a labelled diagram to illustrate
how a chain reaction may occur.
Physics 27 Nuclear Fusion & Birth of Stars
●Compare the uses of nuclear fusion and nuclear fission. Limited to the generation of electricity
●Nuclear fusion is the joining of two atomic nuclei to form a larger one.
●Nuclear fusion is the process by which energy is released in stars
●Stars form when enough dust and gas from space is pulled together by gravitational attraction. Smaller masses may also form
and be attracted by a larger mass to become planets. Candidates should be able to explain why the early Universe contained only
hydrogen but now contains a large variety of different elements.
Physics 28 The Death of Stars
●During the ‘main sequence’ period of its life cycle a star is stable because the forces within it are balanced. The term ‘radiation
pressure’ will not be required.
●A star goes through a life cycle. This life cycle is determined by the size of the star. Candidates should be familiar with the chart
below that shows the life cycle of stars.
●Fusion processes in stars produce all of the naturally occurring elements. These elements may be distributed throughout the
Universe by the explosion of a massive star (supernova) at the end of its life. Candidates should be able to explain how stars are
able to maintain their energy output for millions of years. Candidates should know that elements up to iron are formed during the
stable period of a star. Elements heavier that iron are formed in a supernova.
Physics 26 Nuclear Fission
What is the difference between a nucleus and an atom?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What happens during nuclear fission? (What is there before it happens and what comes out?)
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What are the two fissionable materials that are commonly used and which one is used the most?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Complete this diagram to show how a chain reaction could occur
The diagram shows the cross-section through a nuclear reactor. The control rods, made of boron, are used to control the chain
reaction. Boron atoms absorb neutrons without undergoing nuclear fission. Explain how they would be used to:
Slow the reaction, speed up the reaction and stop the reaction.
Physics 27 Nuclear Fusion & Birth of Stars
What happens during nuclear fusion? (What is there before it happens and what comes out?)
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Is nuclear fission or nuclear fusion most commonly used to generate electricity? ________________________________________
Why? ___________________________________________________________________________________________________
________________________________________________________________________________________________________
The early universe contained only hydrogen but now contains a large variety of different elements. How did this happen?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is a nebula?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Explain how a nebula may form a protostar.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is the difference between a protostar and a main sequence (stable) star?
________________________________________________________________________________________________________
How could the planets have been formed?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Physics 28The Death of Stars
In a main sequence star there are forces acting both inwards and outwards. The force acting inwards is _____________________
What are the forces like in comparison to each other? ____________________________________________________________
How can a star remain stable for millions of years? _______________________________________________________________
________________________________________________________________________________________________________
Why does a star eventually change (as it dies)? __________________________________________________________________
________________________________________________________________________________________________________
List the stages that a star about the same size as the Sun would go through as it dies.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
List the stages that a star that is much bigger than the Sun would go through as it dies.
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What is a black hole and how do you detect one?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
________________________________________________________________________________________________________
Where are all elements made? _______________________________________________________________________________
Where are elements lighter than iron formed? ___________________________________________________________________
Where are elements heavier that iron formed? ___________________________________________________________________
How are elements distributed throughout the Universe?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
What could then happen?
________________________________________________________________________________________________________
________________________________________________________________________________________________________
The diagram, drawn below, places stars in one of four
groups. Where a star is placed on the diagram is
determined by the surface temperature and relative
luminosity of the star. A star with a relative luminosity of 1,
emits the same amount of energy every second as the
Sun.
Use the information in the diagram to describe what will
happen to the Sun after the stable period ends. Make sure
you mention the stages that it goes through.
______________________________________________
______________________________________________
______________________________________________
______________________________________________
______________________________________________
______________________________________________
______________________________________________
______________________________________________