Electricity

Which is the unit of current?

• volts

• amps

• watts

• joules

Which is the unit of voltage?

• volts

• amps

• watts

• joules

Complete the sentence:

The role of the neutral wire in a mains circuit is

• to carry current from the power station to your home.

• to provide a path of least resistance to the ground.

• to resist all current flow.

• to complete the circuit so that current can flow.

Which of the following is an insulator used in plugs?

• copper wiring

• brass pins

• plastic casing

• fixing screws

Where should a switch be placed in a mains circuit?

• connected to the earth wire

• connected to the live wire

• connected to the neutral wire

• anywhere in the circuit

Complete the following sentence:

Electrical power is defined as

• the energy in the circuit.

• the rate of flow of charge.

• the rate of energy transfer.

• the number of electrons in the circuit.

A 1100 W hairdryer is used on the 230 V mains supply. What is the current supplied?

• 2.5 A

• 0.2 A

• 4.8 A

• 0.2 A

A 2 kW kettle is used on a 230 V mains supply. It takes 1 minute 30 seconds to boil. What is the energy delivered to the kettle in this time?

• 2600 J

• 2.6 J

• 180 J

• 180 000 J

Complete the sentence:

An ammeter is a device that measures

• voltage.

• charge.

• current.

• resistance.

Complete the following sentence:

A current is defined as

• stationary electrons.

• the energy in a cell.

• a net flow of charge.

• electrons.