Bitesize has changed! We're updating subjects as fast as we can. Visit our new site to find Bitesize guides and clips - and tell us what you think!

Science

Energy and Electricity

Using electricity - Test

1.

What is the approximate voltage produced by power stations?

2.

Why are transformers used in the National Grid?

3.

A transformer produces 100 V from an input of 50 V. What does this tell you?

4.

A 250W computer is switched on for 4 hours. How many Units of electricity does it use?

5.

A 2 kW electric fire is switched on for 30 minutes. How many Units of electricity does it use?

6.

If one Unit of electricity costs 10p, how much will 30 Units cost?