Download Physical Science Practice Midterm

Physical Science Practice Midterm
o On the actual midterm you will have:
o 25 Multiple choice
o 15 Definitions and examples
o 2 Diagrams
o 5 Essay questions. (MINIMUM 1 paragraph for each)
o 4 Problems
o 1 Essay
o Extra Credit
o Definitions.
o Instantaneous Speed
o Average Speed
o Constant Speed
o Velocity
o Acceleration
o Force
o Inertia
o Friction
o Weight
o Newton’s First Law
o Newton’s Second Law
o Newton’s Third Law
o Terminal Velocity
o Projectile
o Centripetal Acceleration
o Centripetal Force
o Momentum
o Air Resistance
o Kinetic Energy
o Potential Energy
o Mechanical Energy
o Thermal Energy
o Work
o Law of Conservation of Energy
o Temperature
o Heat
o Specific Heat
o Convection
o Conduction
o Radiation
o Insulator
o Heat engine
o Lever
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Pulley
Wheel and Axle
Inclined Plane
Screw and Wedge
Mechanical Advantage
Efficiency
Power
Melting
Freezing
Sublimation
Evaporation
Solid
Liquid
Gas
Heat of Fusion
Heat of Vaporization
Pressure
Buoyant Force
Boyle’s Law
Charles’s Law
Pascal’s Principle
Archimedes’ Principle
Bernoulli’s Principle
Substance
Mixture
Compound
Element
Colloid
Suspension
Tyndall Effect
Smog
Physical Property
Physical Change
Chemical Property
Chemical Change
Law of Conservation of Mass
Atomic Number
Mass Number
Isotope
Proton
Neutron
Electron
Group
Period
Nucleus
Electron Cloud Model
Formulas and Equations to memorize
o v = d/t
Units = _________________
o a = (vf-vi)/t
Units = _________________
o F = ma
Units = _________________
o p = mv
Units = _________________
o W = Fd
Units = _________________
o Q=mCpT
Units = _________________
o MA = Le/Lr
Units = _________________
o MA = rw/ra
Units = _________________
o Efficiency – Wout/Win x 100% = Fr x dr /Fe x de x100%
Units = _________________
o P = W/t
Units = _________________
Problems
Speed/Velocity
o Sound travels at a speed of 330 m/s. If a firecracker explodes
3630 m away from you, how long does it take for the sound of
the explosion to reach you?
Acceleration
o A car’s velocity changes from 0m/s to 60m/s 10 s later. Calculate
the car’s average acceleration.
Force
o A 63kg skater pushes off from a wall with a force of 300N. What
is the skater’s acceleration
Work
o A dancer lifts a 400N ballerina overhead a distance of 1.4m and
holds her there for several seconds. How much work is done
on the ballerina?
Specific Heat
o Calculate the change in thermal energy when 230g of water
warms from 12oC to 90oC. (Specific Heat of water is
4190J/(kgxK)
Mechanical Advantage (Lever)
o A worker uses an iron bar to raise a box weighing 65N. The effort
arm of the lever is 60cm long. The resistance arm is 25cm
long. What is the mechanical advantage of the lever?
Mechanical Advantage (Wheel and axle)
o An automobile steering wheel having a diameter of 48 cm is used
to turn the steering column, which has a radius of 4 cm. What
is the MA of the wheel and axle?
Efficiency (Inclined Plane)
o A sofa weighing 1500N must be placed in a truck bed 1m off the
ground. A worker uses a force of 500N to push the sofa up an
inclined plane that has a slope length of 4m. What is the
efficiency of the inclined plane?
Power
o A figure skater lifts his partner, who weighs 450 N, 1m in 3s.
How much power is required?
Physical Science Honors Study Guide
Chapters 3 to 10
Chapter 3 – Moving Objects
 Describing Motion
o Speed
 Instantaneous
 Average
 Constant
o Calculating Speed
 V = d/t
 Velocity = distance over time
 Units = m/s
o Graphing Speed
 Distance-time graph
 Time on the x-axis, Distance on the y-axis
 Velocity and Acceleration
o Velocity and Speed
 Velocity describes both speed and direction
 Units are same as speed
o Acceleration
 a = (vf-vi)/t =
 Units = m/s2
 Force and Motion
o Force
 A push or a pull one body exerts on another
o Effects of forces on objects
 May or may not change the direction of motion
 Balanced Forces
 Net Force
o Inertia and Mass
o Newton’s First Law
o Friction
 Effects of Gravity
o Gravitational Force
 Gravity
 Gravitational force depends on mass and distance
between objects
o Weight
o Measuring Forces
Chapter 4 – Acceleration and Momentum
 Accelerated Motion
o Newton’s Second Law


 F=ma
o Falling Objects
 Air Resistance
 G= 9.8m/s2
o Terminal Velocity
Projectile and Circular Motion
o Projectiles
 Horizontal Motion
 Vertical Motion
o Moving in Circles
 Centripetal Force
 Centripetal Acceleration
o Weightlessness in orbit
 Elevators and freefall
Action and Reaction
o Newton’s Third Law
 Action-Reaction Pairs
o Momentum
 Momentum = mass x velocity; p = m x v
 Units of momentum are kg x (m/s)
o Law of Conservation of Momentum
Chapter 5 – Energy
 Energy and Work
o Kinetic and Potential Energy
 Kinetic Energy
 Potential Energy
 Units are Joules
o Work
 Work = Force x distance = F x d
 Work, like Energy is measured in joules
o Conservation of Energy
 Mechanical Energy
 Law of Conservation of Energy
 Figure 5-7; pg. 115 (Where are KE and PE greatest,
least, etc)
 Temperature and Heat
o Temperature
o Thermal Energy
 Includes Kinetic and Potential Energies
o Heat
 Measured in joules
 Measuring Thermal Energy
o Specific Heat





Measured in J/(kg x K)
Denoted by Cp
Q = change in thermal energy
m = mass
 Tfinal - Tinitial
Cp = specific heat(usually given)


Chapter 6 – Using Thermal Energy
 Moving Thermal Energy
o Conduction
 The transfer of energy through matter by direct
contact.
 Takes place in solids, liquids, and gases.
o Convection
 The transfer of energy by the movement of matter.
 The matter must move from one place to another.
 Only fluids can flow freely (liquids or gases).
o Radiation
 The transfer of energy in the form of waves.
 Matter is not needed for radiation.
o Insulators
 Insulators do not allow heat to move easily through
them.
 Heating Systems
o Simple heating systems
 Fire
 Stove
o Radiator – device with a large surface area designed to heat
the air near it by conduction.
o Can be heated by electricity
o Steam heating system
o Forced air heating system
o Solar heating
 Passive
 Active - use mechanical devices to transfer heat.
 Using Heat to Do Work
o Heat engines - Devices that convert thermal energy into
mechanical energy by combustion (burning fuel).
 Internal combustion engine
 Fuel burns inside cylinders in the engine.
 Each cylinder has a piston inside that moves up
and down.
 On each end of the cylinder is a valve.
 Pistons move and turn a crankshaft.


The crankshaft turns and causes the axles and
wheels to turn.
The four stroke cycle:
o Intake stroke - intake valve opens and
draws in a fuel-air mixture.
o Compression stroke - intake valve closes
and the piston moves up, compressing the
fuel-air mixture.
o Power stroke - a spark plug ignites the
fuel-air mixture which forces the piston
down.
o Exhaust stroke - the piston moves up and
the exhaust valve opens to let out the
waste from the burning.
Chapter 7 – Machines
 A machine is a device that makes work easier.
 A machine makes work easier by changing the force you exerted
on it in size, direction or both.
 When you use a simple machine, you are trying to move
something that resists being moved.
o The weight of the object (the force that gravity exerts
on the object) is what makes the object resist the work.
o The machine allows us to move the object regardless of
the resistance.
 Two forces are involved when a machine is used to do work.
o Effort Force (Fe) = the force applied to the machine
o Resistance Force (Fr) = the force applied by the
machine to overcome resistance due to gravity or
friction.
o Work done on the machine is called Work input (Win)
o Work done by the machine is called Work output (W
out)
o Win = Fe x de
W out = Fr x d r
o

o You can never get more work out of a machine than
you put in.
o (W out) can never be greater than (Win)
In an ideal machine, Win = Wout
o In this system Fe x de = Fr x dr
o In most cases, a machine multiplies the force applied
to it, Fr is greater than Fe
o The machine multiplies your effort but you must move
the handle a greater distance.
o Mechanical Advantage (MA) = the number of times a
machine multiplies the effort force
o MA = resistance force/effort force =Fr/Fe



A simple machine is a device that does work with only one
movement.
A combination of two or more simple machines is a compound
machine.
o Often the simple machines that make up a compound
machine are concealed
 A bicycle is an example of a compound machine
 Pedal – wheel and axle system
 Seat – connected to the bike with a Screw
 Hand brake - Lever
 Overall mechanical advantage (MA) of a bicycle is
the ratio of the resistance force exerted by the tires
on the road to the effort force exerted by the rider
on the pedals.
All six types of simple machines are variations of two basic
machines: lever and inclined plane.

There are 6 types of simple machines…
o Lever
o Pulley
o Inclined Plane
o Screw
o Wedge
o Wheel and axle

Lever
o A bar that is free to pivot or turn about a fixed point.
o The fixed point is called a fulcrum.
o The part of the lever on which the effort force is applied is
called the effort arm. The part of the lever that exerts the
resistance force is called the resistance arm.

Pulley
o A grooved wheel with a rope or a chain running along the
groove.
o Can be fixed or movable
o Fixed pulley – attached to something that doesn’t move.
o Movable pulley – attached to the object being moved.
o Fixed and moveable pulleys can be combined to form a
block and tackle.
o MA = Length of effort arm
Length of resistance arm


Wheel and axle
o A machine consisting of two wheels of different sizes that
rotate together.
o Effort force is usually applied to the larger wheel.
o The resistance force is exerted by the smaller wheel,
which is the axle.
o Radius of the wheel is the effort arm, and the radius of
the axle is the resistance arm. The center of the axle is
the fulcrum.
o MA = radius of wheel
radius of axle
Inclined Plane
o A sloping surface used to raise objects.
o Ex. Ramp
o MA = effort distance = length of slope
resistance distance height of slope

Screw and Wedge
o Screw - An inclined plane wrapped in a spiral around a
cylindrical post
o Wedge – an inclined plane with one or two sloping sides.

Efficiency
o The measure of how much of the work put into a machine is
changed to useful work put out by a machine.
o The higher the efficiency of a machine the greater the
amount of work input is changed to useful work output.
o Efficiency = Wout x 100% = Fr x dr x 100%
Win
Fe x de
Power
 The rate at which work is done.
 The measure of the amount of work done in a certain
amount of time.
 To calculate power, divide the work done by the time
required to do the work.
 Power = Work (in Newtons) / Time (in seconds)
 Power = W
measured in watts (W)
t

Chapter 8 – Matter
State
Solid
Liquid
Gas
Plasma
Properties
Particle
Examples
Description
Definite Shape
Closely packed; do Ice, sugar
and volume
not easily change
position
Definite volume; Closely packed;
Milk,
takes shape of
able to move past Mercury in
container.
one another
thermometer
Occupies shape Spread apart; free Oxygen,
and volume of
to move in all
steam
container
directions
Occupies shape Gas like mix of
Mercury
and volume of
negatively and
vapor in
container
positively charged fluorescent
particles
tube, sun
and stars
Pressure
 The total amount of force exerted by a gas depends on the size
of its container. Pressure is the amount of force exerted per unit
of area.
o P=F/A
o The pascal (Pa) is the SI unit of pressure. Most pressures are
measured in kPa (kilopascals)
o Earth’s atmosphere exerts a pressure on everything within it.
At sea level, atmospheric pressure is 101.3kPa.
Boyle’s Law
 The pressure of a gas depends on how often its particles strike the
walls of the container. If you squeeze some gas into a smaller
space, its particles will strike the walls more often, giving it
increased pressure.
 According to Boyle’s law, if you decrease the volume of a container
of gas, the pressure of the gas will increase, provided the temp.
Does not change.
 Increasing the volume would cause the pressure to drop.

Charles’ Law
 According to Charles’s Law, the volume of a gas increases with
increasing temperature, provided that the pressure doesn’t change.
 A gas shrinks with decreasing temperature.
 As a gas is heated, its particles move faster and faster, and its
temp. Increases. Because the gas particles move faster, they begin
to strike the walls of their container more often and with more
force. If the walls are free to move, the gas pushes the walls out
and expands.
Pascal’s Principle
 The ideal press consists of two pistons of areas ( a , A )
enclosed between them incompressible liquid as in figure
When a small force ( f ) acts on the small piston ( a ) , it exerts
a pressure ( p = f/a ).
 The increase in pressure P is equally transmitted to every part of
the liquid & to the walls of the container according to Pascal's
Principle till it acts on the large piston ( A ) to produce very large
force ( F = P x A ) causes the load to rise .
 To keep the large piston (A) at equilibrium with the small one (a) a
load = F is placed on the large piston .

P = f/a = F/A
Archimedes Principle
 According to Archimedes’ Principle, the buoyant force on an object
in a fluid is equal to the weight of the fluid displaced by the object.
Bernoulli’s Principle
 As the velocity of the fluid increases, the pressure exerted by the
fluid decreases
 Fluids flow faster when they are forced to flow through narrow
spaces.
 The reduction in pressure in these spaces is an example of
Bernoulli’s principle called the Venturi effect.
Chapter 9
Substances
A substance is either an element of a compound.
 An element is a kind of matter in which all atoms are alike.
Examples – Hydrogen, Carbon, Fluoride
 A compound is a material made of two or more elements that
are combined.
Examples – H2O, CO2
 An atom is a particle that makes up all matter.
Mixtures
A mixture is a material made up of two or more substances.
Mixtures do not always contain the same amounts of different
substances.
 Heterogeneous mixture – a mixture in which different
materials can be easily distinguished
Example – A solution with oil and water
 Homogeneous mixture (solution) – a mixture in which two or
more substances are uniformly spread out.
Example – A solution of salt and water.
Colloids and Suspensions
A colloid is a heterogeneous mixture that, like a solution, never
settles.
 Examples – Gelatin, milk
A suspension is a heterogeneous mixture containing a liquid in
which visible particles settle.
 Examples – Muddy water
Tyndall Effect
The scattering of light by particles in a mixture.
We can see the Tyndall effect in colloids.
Smog
Smog is a form of air pollution.
It is a colloid of small invisible pieces of solid materials mixed with
the gases that make up air.
Some of the solid particles that make up smog are dust.
Unburned compounds in automobile exhaust accounts for most of
the particles in smog.
Warm air rises in the atmosphere.
 However, this warm air may be trapped beneath a layer of
colder air.
 The combination of the warm and cold air causes the colloid
smog.
Physical Properties
A physical property is any characteristic of a material that you can
observe without changing the substances that make up the
material.
Appearance and behavior
 Shape
 Color
 Size
 Density
 Melting point
 Boiling point
Physical Change
A change in size, shape or state of matter.
When a substance freezes, boils evaporates, sublimes or
condenses, it undergoes physical change.
A color change indicates a physical change.
Physical changes do not change the identities of the substances in
a material.
Chemical Change
A change of one substance in a material to a different substance.
Examples include:
 Fireworks exploding
 Matches burning
 Rotten eggs
 Burned toast
 Rusty tires (exposed to oxygen)
 Odor is a clue that a chemical change has occurred.
 Burning and rusting are chemical changes because new
substances are produced.
Chemical Property
A characteristic of a substance that indicates if it can undergo a
certain chemical change.
 Flammable or combustible substances.
Law of Conservation of Mass
Matter is neither created nor destroyed during a chemical change.
When we burn something, there is no loss of mass.
 (Add the oxygen in the air with the log that burned)
Chapter 10 – Elements and the Periodic Table
I. Structure of the Atom
a. Chemical Symbols
b. Matter and Atoms
i. Atomic Number
ii. Nucleus
1. protons
2. neutrons
iii. electrons
c. Models of Atoms
i. Electron Cloud Model
d. Energy levels of Electrons
i. Electrons near the nucleus have low energy
ii. Electrons farther away have higher energy
1. 1st level = 2 electrons
2. 2nd level = 8 electrons
3. 3rd level = 18 electrons
4. 4th level = 32 electrons
a. We must assume that 8 electrons is
complete and stable
II. Masses of Atoms
a. Atomic Mass unit
b. Mass number = protons + neutrons
c. Isotopes = same proton number, different neutron number
III. The Periodic Table
a. Structure of Periodic Table
b. Groups of Elements – vertical columns
c. Periods of Elements – horizontal rows
i. Alkali
ii. Alkaline Earth
iii. Transition
iv. Halogens
v. Noble Gases
vi. Metalloids
vii. Non-metals