the electricity from electric sockets and circuits in a home

a brown wire in a mains circuit that has a voltage of ±230 V

a blue wire in a mains circuit that has a voltage of 0 V

a current passing through a person’s body that can be painful and sometimes harmful

a property of materials that makes it harder for current to flow

Danger from electric shock

Combined science

Short circuits and earth wires

Power of an appliance or electric circuit

Calculating with electric charge

The National Grid

Energy resources

In the Circuit components unit, pupils learnt how the resistance of filament lamps and diodes change with current and about the properties and applications of light dependent resistors and thermistors.

This unit covers UK domestic a.c. supply, mains wiring safety, energy changes in electrical systems, power ratings, and energy transfer. It explains the National Grid, transformers, energy sources, and calculations for energy changes and power transmission efficiency.

Mains electricity

Subjects which particular individuals may be sensitive to, eg, adoption, migration, bereavement or death, divorce, poverty, deprivation.

Depiction or discussion of sensitive content

Mains electricity is AC, which stands for …

What colour is the insulation of the neutral wire in a mains circuit?

What is the voltage of the live wire in a UK mains circuit?

touching the ground and a live wire at the same time

touching a neutral wire and a live wire at the same time

touching a neutral wire and the ground at the same time

Which of the following cause an electric shock?

Wet skin increases the current during a shock.

Wet skin increases the voltage during a shock.

Wet skin has a higher resistance than dry skin.

Wet skin has a lower resistance than dry skin.

Which of the following explains why it is much more dangerous to get an electric shock when your skin is wet than when your skin is dry?

A person gets an electric shock from the mains. Their skin has a resistance of 25 kΩ. The current through their body is {{}} A.

A battery provides DC, which stands for …

Which of the following equals a milliamp?

A series circuit contains a battery and some resistors only. The connections to the battery are swapped. Which of the following statements about the effect of this change is correct?

In a circuit, the current and p.d. determine the resistance.

In a circuit, the p.d. and resistance determine the current.

In a circuit, the resistance and current determine the p.d.

Which of the following statements is correct?

How many of the following are good electrical conductors? rubber, copper, tap water, sea water

One terminal of a power supply has a voltage of +5 V and the other terminal has a voltage of −2 V. Which of the following is the potential difference across the power supply?

Danger from electric shock

Lesson outcome

Content guidance