Question

When the current is switched on through a wire, a compass needle kept nearby gets deflected from its north-south position. Explain.

Answer 1

The flow of current through a wire

1. When electrons move through a wire from the negative terminal to the positive terminal, it is considered as the current flowing through the wire.
2. The direction of the current however taken as the opposite of the flow of the current.
3. Due to the flow of current through the wire, the wire starts to behave like a magnet, as a magnetic field is generated.
4. When the current is increased, the magnetic effect also increases, since the magnitude of the magnetic field is directly proportional to the electric current.

Because of this magnetic field, when a compass needle is brought closer to the wire, it gets deflected from its north-south position.