Which of the following does not contain electromagnets?*1 pointElectric bellRelayCircuit breakersElectric heater

To determine which of the options does not contain electromagnets, let's analyze each one:

1. Electric Bell: An electric bell uses an electromagnet to attract a hammer that strikes the bell, producing sound.

2. Relay: A relay is an electromagnetic switch that uses an electromagnet to operate the switching mechanism.

3. Circuit Breakers: Some types of circuit breakers use electromagnets to trip and interrupt the circuit when there is excess current.

4. Electric Heater: An electric heater typically consists of heating elements that convert electricity into heat but does not use electromagnets for its basic operation.

Final Answer

The option that does not contain electromagnets is Electric Heater.