Fixing faulty circuits | Exit Quiz | Oak National Academy

Which device can be used to check if a component is working correctly?

• multimeter

• ammeter

• voltmeter

• battery

Answer explanation

A multimeter can be used to test electrical components in a range of ways, e.g. for determining the voltage of, the current through and resistance of a component.

Which of these is needed to allow electricity to flow around a circuit?

• only one component

• lots of batteries

• no gaps between the components

• multiple loops

Answer explanation

A complete circuit is required to allow electricity to flow.

What is the name of the fine wire found in some types of bulb that glows when electricity passes through it?

• an element

• a component

• a fuse

• a filament

Answer explanation

The fine wire in some bulbs is called a filament. Other bulbs, such as fluorescent and LED's do not contain filaments.

In this circuit, every component works as it should until one of the bulbs blows. Which statement correctly predicts what will happen to the other components?

• The motor will spin faster but the other bulb will get dimmer.

• The motor will spin faster but the other bulb will get brighter.

• The other bulb and motor will stop working.

• The other bulb and motor will continue working as before.

Answer explanation

If one bulb blows, the circuit is incomplete. This means that no electricity can flow so the motor and other bulb will stop working.

Which of these could cause an electrical cable not to work?

• The cable could be too long.

• The metal wire inside the cable can break or get disconnected.

• The cable is not the correct colour.

• The cable is not correctly connected to a component.

Answer explanation

Electrical cables work whether they are long or short. They have a metal wire inside which is needed to complete a circuit. If this wire breaks or gets disconnected, the cable will not work.

Which of these will cause a series circuit to stop working if the filament inside a bulb breaks?

• The bulb is rated too high.

• The bulb is not fully screwed into the holder.

• The filament has melted.

• The filament gets very hot.

Answer explanation

If the bulb is not connected correctly, there is no contact between the bulb and the wires. This creates a gap in the circuit so the circuit is incomplete. If the filament melts, a gap will also be created.