Uses of Electromagnets

Select the advantages of electromagnets over permanent magnets.

• Can be turned on and off

• Heat up quickly

• Their strength can be altered

• They require electricity

What is this?

when the current is too large a solenoid attracts an iron lever which makes the contacts spring apart.

• Speaker

• Circuit Breaker

• Electric Bell

• Relay Switch

• Microphone

What is this?

a small potential difference causes a current through an electromagnet that causes a switch in a second circuit, with a larger potential difference, to close.

• Speaker

• Circuit Breaker

• Electric Bell

• Relay Switch

• Microphone

What is this?

a vibration causes a diaphragm to move. this is attached to a coil that moves and vibrates relative to a permanent magnet. this creates an alternating current to flow.

• Speaker

• Circuit Breaker

• Electric Bell

• Relay Switch

• Microphone

an alternating current causes a coil to vibrate around a permanent magnet. this, in turn, makes a paper cone vibrate.

• microphone

• speaker

• helicopter

• electric toothbrush