What is the function of brushes in an electric generator?

What change should be made in an a.c. generator so that it may become a d.c. generator?

State whether the following statements are true or false:

(a) A generator works on the principle of electromagnetic induction.

(b) A motor works on the principle of electromagnetic induction.

When a wire is moved up and down in a magnetic field, a current is induced in the wire. What is this phenomenon known as?

When current is 'switched on' and 'switched off' in a coil, a current is induced in another coil kept near it.

What is this phenomenon known as?