Science: Chapter 13 Electrical

What can happen when a person comes into contact with an exposed wire?

Electrical current can pass through the person's body and cause an electric shock.

What can an electric shock cause?

It can cause pain and potentially serious injury.

What is the purpose of a fuse?

To limit the amount of current flowing through a circuit.

What is a fuse made of?

A thin piece of wire that melts when too much current flows through it.

What happens when excessive current flows through a fuse?

The fuse wire heats up and melts, breaking the circuit.

Why does a fuse protect electrical appliances?

It breaks the circuit when the current becomes too large, preventing excessive current from continuing to flow.

What is a circuit breaker?

A safety device that automatically breaks a circuit when excessive current flows.

What happens when excessive current flows through a circuit breaker?

The circuit breaker trips and breaks the circuit.

Why are heating elements made from materials with high resistance?

A high resistance causes more electrical energy to be converted into thermal energy when current flows through it.

What is the lighting effect of an electrical current?

The heating effect of an electrical current can cause a material to become hot enough to produce light.

What is the formula for electrical energy consumption in kWh?

Electrical energy (kWh) = Power (kW) × time (h)