1. Inform you about time table of exam.
2. Inform you about new question papers.
3. New video tutorials information.
- Alternating current : frequency of AC
State whether the following statements are true or false.
An electric motor converts mechanical energy into electrical energy.
Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?
A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (i) pushed into the coil, (ii) withdrawn from inside the coil, (iii) held stationary inside the coil?
A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes once in each
(a) two revolutions
(b) one revolution
(c) half revolution
(d) one-fourth revolution
The device used for producing electric current is called a
The essential difference between an AC generator and a DC generator is that
(a) AC generator has an electromagnet while a DC generator has permanent magnet.
(b) DC generator will generate a higher voltage.
(c) AC generator will generate a higher voltage.
(d) AC generator has slip rings while the DC generator has a commutator.