Grade 9 · Science · Unit 9 of 10
Making Electricity
Generators, power sources and staying safe with electricity.
What your child practises
Practises how electricity is generated and carried, including Manitoba's hydroelectric stations, the advantages and drawbacks of different sources, AC and DC, and electrical safety.
Manitoba Curriculum learning outcome: SCI.9.E.8, SCI.9.E.12, SCI.9.E.13, SCI.9.E.14 · alternating and direct current, generating electricity, hydroelectricity and electrical safety
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
A fuse or circuit breaker protects a circuit by…
- raising voltage
- stopping the current when it is too high
- storing charge
Show answer
stopping the current when it is too high
Hint: It prevents overheating and fires.
Question 2
Which item keeps people safe from electric shock in a bathroom outlet?
- a ground fault circuit interrupter (GFCI)
- an extra plug
- a longer cord
Show answer
a ground fault circuit interrupter (GFCI)
Hint: A GFCI cuts power when it senses current leaking.
Question 3
Alternating current changes direction…
- never
- many times each second
- once an hour
Show answer
many times each second
Hint: Household electricity in Canada alternates 60 times per second (60 Hz).
Question 4
A downside of fossil fuel power plants is that they…
- make no electricity
- release carbon dioxide
- use no fuel
Show answer
release carbon dioxide
Hint: Burning fuels adds greenhouse gases to the air.
Question 5
Solar panels (photovoltaic cells) change…
- sound into heat
- wind into light
- light energy into electrical energy
Show answer
light energy into electrical energy
Hint: Sunlight knocks electrons loose to make a current.
Question 6
Which source uses a turbine that is spun by steam from heated water?
- a wind farm
- a solar panel
- a coal plant
Show answer
a coal plant
Hint: Many power plants boil water to make steam that turns turbines.