Question

Explain the principle of an electric generator and the function of brushes.

Answer 1

Step 1: Principle of Electric Generator:

1. An electric generator works on the principle of the electromagnetic induction phenomenon.
2. Here a coil is rotated between two magnetic poles which results in the flow of an induced current inside the coil.
3. The direction of this induced current is given by Fleming's right-hand rule.

Step 2: Working of electric generator:

1. Electric generators work on the principle of electromagnetic induction.
2. Between the poles of a horseshoe-type magnet, a conductor coil is rotated rapidly.
3. The conductor coil along with its core is known as an armature.
4. A shaft of a mechanical energy source such as a motor is connected to the armature and rotated.
5. When the coil rotates, it cuts the magnetic field which lies between the two poles of the magnet.
6. A flow of electric current will be induced inside the conductor due to the interference of the magnetic field.

Step 3: The function of Brushes

1. Brushes are kept pressed onto two slip rings separately.
2. The outer ends of the brushes are connected to the galvanometer.
3. Thus, brushes help in transferring current from the coil to the external circuit.