Single Phase and Three Phase Generator

Q. 2 coils of self inductance to 2MH and 8 MH are placed so close together that the effective flux in one coil is completely linked with the other the mutual inductance between these coil is

Q.

What does the given diagram represent?

1. It represents a single-phase generator.

2. It represents a three-phase generator.

3. It represents a moving coil microphone.

4. It represents the armature of an AC generator.

Q. In a three phase generator electricity is produced due to the .

1. moving magnet
2. moving coil
3. stationary magnet

Q.

The transformation ratio in the step-up transformer is

1. one

2. greater than one

3. less than one

4. the ratio greater or less than one depends on the other factors

Q.

In power generators, three armature coils are arranged around the field magnet at an angular separation of ____

1. ${120}^{\circ }$

2. ${90}^{\circ }$

3. ${100}^{\circ }$

4. ${360}^{\circ }$

Q. In a three phase transformer, there are three magnetic flux's in the core differing in time phase bydegree.

1. 120
2. 60
3. 180

Q. What is the self inductance of a solenoid of length $31.4$cm, area of cross-section ${10}^{-3}{m}^2$ and total number of turns ${10}^3$?

1. $4$mH
2. $4$H
3. $40$H
4. $0.4$H

Q. The arm of an electric generator with split rings is rotated in clockwise direction. The deflection of the galvanometer will _______.

1. be towards left
2. be towards right
3. oscillates between left and right.
4. Can not be determined

Q.

In a $DC$ generator, the induced $e.m.f$ in the armature is

1. $DC$

2. $AC$

3. fluctuating $DC$

4. both $AC$ and $DC$

Q. The arm of an electric generator with split rings is rotated in clockwise direction. The deflection of the galvanometer will _______.

1. be towards right
2. be towards left
3. Can not be determined
4. oscillates between left and right.

Q. The arm of an electric generator with split rings is rotated in clockwise direction. The deflection of the galvanometer will _______.

1. be towards left
2. be towards right
3. oscillates between left and right.
4. Can not be determined

Q.

_____ has only one set of coils in between the pole pieces of the field magnet.

1. A single phase generator

2. A three phase generator

3. A transformer

4. A microphone

Q. How is the mutual inductance of coils affected when a thin iron sheet is placed between the coils , other factors remaining the same? Explain ur answer.

Q. nttwo circular coil 1 and 2 are made from same wire bt radius of ist coil is twice of 2 nd coil . what is the ratio of potential differrence applied across them , so that the magnetic field at the centre is the samen

Q. The arm of an electric generator with split rings is rotated in clockwise direction. The deflection of the galvanometer will _______.

1. be towards right
2. oscillates between left and right.
3. Can not be determined
4. be towards left

Q. A uniform magnetic field exists in the plane of paper point from left to right as shown in figure. In the field, an electron and a proton move as shown. The electron and the proton experience forces.

1. Both pointing into the plane of paper
2. Both pointing out of the plane of paper
3. pointing into the plane of paper and out of the plane of paper, respectively
4. pointing opposite and along the direction of the uniform magnetic field respectively.