Download Science Focus 9 – Unit 4 – Unit Review Topic 1 – Electric Charges

Science Focus 9 – Unit 4 – Unit Review
Topic 1 – Electric Charges
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
What is static electricity and why is it called static?
What is the charge on each of the particles that make up the atom?
What are the two particles in the nucleus of the atom?
Which particle rotates around the nucleus?
Which particle moves between objects when they are rubbed together?
What are the three parts of the Law of Charges?
What is the difference between an insulator and a conductor?
Name 3 conductors and 3 insulators.
What is a superconductor? In what conditions do superconductors work best?
What does it mean when we ‘ground’ electricity?
Topic 2 – Electricity within a circuit
1.
2.
3.
4.
5.
6.
7.
8.
What is the energy transformation that takes place in a cell?
What is a battery?
Name the 4 common items we would find in an electric circuit.
Which particle flows through the wires in a circuit and what is this flow called?
Draw a circuit diagram with 1 battery, 1 lamp and 1 switch.
What are current and voltage measured in?
What instrument do we use to measure a large current? A small current?
How do current and voltage differ?
Topic 3 – Resisting the movement of charge
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
What is the purpose of a resistor?
What is the difference between a resistor and an insulator?
What is resistance measured in and what is the symbol for it?
What is Ohms Law? What do the three variables represent?
A circuit has a voltage of 8V and current of 2A. What is the resistance?
What is a variable resistor and what are some examples?
What is the difference between a series circuit and a parallel circuit?
What happens to the current in a series circuit? A parallel circuit?
What are the 4 factors affecting the resistance of wires?
Draw a parallel circuit containing 2 resistors on separate loops, 1 battery and 1 switch.
What is the voltage in a circuit when we connect four (4) 1.5 V cells together?
Topic 4 – The Energy Connection
1. Energy is the ability to do what?
2. Name 2 devices that convert electrical energy to heat.
3. What does a thermocouple do and how does it work? What do we call a collection of
thermocouples?
4. What is a thermoelectric generator?
5. What is a piezoelectric crystal? How does this relate to the conversion of movement into
electricity?
6. Explain how a BBQ lighter uses the piezoelectric effect in reverse to create a fire at its tip.
7. Name 3 devices that convert electricity to light.
8. How do photovoltaic cells work? What is the energy conversion in a photovoltaic cell?
Topic 5 – Portable Power
1. What is an electrochemical cell?
2. What are the two types of electrochemical cells and give an example of each.
3. Fill in the four blanks on this diagram of an electrochemical cell.
4. In our potato cell lab, what acted as the electrodes? Which was the anode and which was the
cathode?
5. What acted as the electrolyte in this experiment?
6. You may have to look this one up. What is electroplating and what is it used for?
Topic 6 – Generators and Motors
1.
2.
3.
4.
5.
Give 3 examples of mechanical energy.
Generators convert ________________ energy into _______________________ energy.
Motors convert ______________________ energy into ____________________ energy.
If you take a wire, wrap it around an iron core and run a current through it, what do you create?
Give 3 ways to make an electromagnet stronger.
6. What did Michael Faraday discover about moving a wire near a magnet?
7. What are the two types of generators?
8. What is the difference between the commutator of an AC generator and a DC generator? Why
do they need to be different?
9. Draw a diagram of an electric generator and label the armature, commutator, brushes and state
whether it is DC or AC.
10. How is a motor similar to a generator? How is it different?
11. Why do DC motors and generators have to use a split ring commutator?
Topic 7 – Electricity in the home
1. What is a transformer and why do we need them?
2. What is the difference between a step-up transformer and a step down transformer?
3. Draw a diagram showing the path electricity takes from a generating plant, through power lines
and eventually into your electrical outlet.
4. How does a circuit breaker work? Why are circuit breakers better than fuses?
5. What is a branch circuit?
6. Explain how microcircuits and regular circuits are similar and different.
7. What is power? What are the two equations we would use to calculate power?
8. What are the units of power and energy?
9. A current of 20 A passes through an electric towel heater when it is connected to a 110V wall
outlet. What is the power of the towel heater?
10. How do you find kilowatt hours?
11. Why would we care about an Energuide label?
12. What is the Law of Conservation of Energy? What are the 2 ways most systems lose energy?
13. What is efficiency and how do you calculate it?
14. Calculate the efficiency of a 500W kettle that takes 10 minutes to boil. To heat the water to
boiling point it takes 196 000 J of energy. What is the efficiency?
15. What is more important to consider when assessing the danger of electricity: current or
voltage?
Topic 8 – Energy Production and the Environment
1.
2.
3.
4.
5.
6.
7.
8.
How do we produce electricity from fossil fuels?
Why is it a better choice to use biomass than fossil fuels?
Name 3 reasons why fossil fuels negatively affect the environment.
How do hydroelectric dams produce electricity?
How do nuclear power plants produce electricity?
What is the negative effect of thermal pollution?
What is cogeneration?
Name all 8 energy sources that we discussed in class.