Revision - Unit 2 - Electricity

Which electricity comes from a power plant to your home?

• Mains

• Battery

Which wires are used to transmit a lot of electricity from the power plant to the city?

• Thick wires

• Thin wires

Electricity from a battery is ...

• AC (Alternating current)

• DC (Direct current)

Mains electricity is ...

• AC (Alternating current)

• DC (Direct current)

AC is usually used in (1) while DC is better for (2).

• 1 - large heavy appliances

  2 - small delicate appliances

• 1 - small delicate appliances

  2 - large heavy appliances

Power is ...

• the rate of flow of electricity.

• the potential difference (pressure)

• the rate at which work is done or energy is used.

There is a current of 0.25 A in a bulb when a voltage of 12 V is applied across it. Calculate the power of the bulb.

• 1 W

• 1.5 W

• 3 W

• 7.5 W

The filament in a bulb has a ... resistance.

• high

• low

Which wire can transmit electricity more easily?

• A

• B

Which wire has a higher resistance?

• A

• B