Self Induction

Q.

In self induction, ___.

1. an emf is induced because of varing magnetic field due to the flow of an AC through the solenoid
   

2. the flow of a direct current changes the magnetic flux associated with the coil

3. an emf is generated in direction opposite to applied emf

4. the flow of an alternating current does not change the magnetic flux associated with the coil

Q.

The change in magnetic flux due to the flow of an AC in a solenoid will generate a back emf in the same solenoid in a direction opposite to that applied to it. Name this phenomenon.

1. Hysteresis

2. Self Induction

3. Electromagnetic Induction

4. Mutual Induction

Q.

Changing a current in a coil produces EMF in the same coil. This phenomenon is known as

1. Mutual induction

2. Self induction

3. Self conduction

4. mutual conduction

Q. The phenomenon in which a changing current in a coil induces an emf in itself is called.

1. Mutual induction
2. Self induction
3. magnetism

Q.
The figure shows two copper wires, A and B. A is straight and B is coiled. So, wire B has self inductance the wire A

1. lower than
2. higher than
3. same as

Q.

A solenoid that is carrying current has magnetic field lines similar to that of ____.

1. a horse-shoe magnet

2. a bar magnet

3. any current carring conductor

4. a spherical magnet

Q.

If the key in the arrangement, in the given figure, is taken out (the circuit is made open) and magnetic field lines are drawn over the horizontal plane ABCD, the lines are:

1. concentric circles.

2. Elliptical in shape

3. Straight lines parallel to each other

4. Concentric circles near the point O but of elliptical shapes as we go away from it.

Q. An induction coil stores 32 joules of magnetic energy and dissipates energy as heat at the rate of 320 watts. When a current of 4 amperes is passed through it. Find the time constant of the circuit when the coil is joined across a battery.

1. 0.2 s
2. 0.1 s
3. 0.3 s
4. 0.4 s

Q. When the current changes from +2 A to – 2A in 0.05 second, and e.m.f. of 8 V is induced in a coil. The coefficient of self – induction of the coil is

1. 0.1 H
2. 0.4 H
3. 0.04 h
4. 5 H

Q. Assertion :An ac generator is based on the self inductance of the coil. Reason: Self inductance involves two coils.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect