Inductors

Q.

What are the factors that affect inductance?

Q. What is variable resistance ? Explain with real life example.

​​​​​​

Q.

Why are pole pieces of galvanometer made concave?

Q.

An inductor does not allow sudden changes in:

1. Inductance

2. Resistance

3. Current

4. Voltage

Q.

Inductance is directly proportional to the length of the coil.

1. True

2. False

Q.

In an iron cored coil , if the iron core is removed how will it affect the inductance of the coil?

1. the inductance will decrease

2. the inductance remains the same

3. the inductance increases and then decrease after a time

4. the inductance will increase

Q.

What does a galvanometer measure?Explain.

Q.

In a dead beat galvanometer, the coil is wound on a frame made of:

Q.
A coil of insulated wire is connected to a galvanometer. What would be seen if a bar magnet with its south pole towards one face of the coil is moved quickly toward and away from it.

1. the galvanometer is deflected towards the left.
2. the deflection of galvanometer is random
3. the galvanometer is deflected towards the right.
4. the deflection of the galvanometer is zero

Q. Two circular coils A and B of insulated wires are kept close to each other.Coil A is connected to a galvanometer whereas coil B is connected to a battery through a key.What will you observe in Coil A if:-
i)Current is passed through B by plugging the key
ii)The current is stopped by removing the key
iii)Both the coils are moved in same direction with the same speed
Explain your answer with the phenomenon invovlved

Q. Explain Faraday's experiment?

Q.

A coil connected to a battery is placed (primary coil) is placed next to another coil (secondary coil) connected to a galvanometer (no battery). What will you observe when:

i) Current in the primary coil is switched on

ii) Current becomes steady in the primary coil

1. i) Deflection is observed in the galvanometer and ii) Deflection in the galvanometer remains constant

2. i) No deflection is observed in the galvanometer and ii) Deflection is observed in the galvanometer

3. i) The needle of the galvanometer remains at zero mark and ii) Deflection is observed in the galvanometer

4. i) Deflection is observed in the galvanometer and ii) No deflection is observed in the galvanometer

5. i) Deflection is observed in the galvanometer and ii) Deflection in the galvanometer is in the opposite direction

Q. If current is made to flow in the anti-clockwise direction through a circular coil; a magnetic north pole is generated.

1. False
2. True

Q.

What is difference and use of ammeter and galvanometer?

Q. Name the scientist who discovered the electromagnetic induction?

1. Galileo
2. Ampere
3. Faraday
4. Oersted

Q.

The diagram shows a coil connected to a centre zero galvanometer G the galvanometer shows a deflection to the right when the N - Pole of a powerful magnet is moved the the right as shown:

State the observation in G when, both the coil and the magent, are moved to the right at the same speed.

1. Change in magnetic flux induces a current in the coil

2. Zero deflection will be seen in the Galvanometer

3. Clockwise current is induced at end A

4. Deflection will be to the right in the galvanometer

Q.

The given figure shows a coil connected to a centre zero galvanometer G. The galvanometer shows a deflection to the right when the N-pole of a powerful magnet is moved to the right as shown.

State the observation in the galvanometer G when the coil is moved away from N.

1. Galvanometer needle will not deflect

2. Galvanometer needle will point at zero position

3. Galvanometer needle will deflect to right

4. Galvanometer needle will deflect to left

Q.

Explain with an experiment principle of Electromagnetic induction. Which law will give the direction of electric current?

Q. What is always the same in the primary coil and the secondary coil of an ideal transformer?

1. Current
2. Power
3. Voltage
4. Resistance

Q. How to find the nearest and next nearest coordination number of BCC?

Q.

The given figure shows a coil connected to a centre zero galvanometer G. The galvanometer shows a deflection to the right when the N-pole of a powerful magnet is moved to the right as shown.

What will be the observation in G when both the coil and the magnet are moved to the right at the same speed?

1. Galvanometer needle will not show any deflection as there is no current induced

2. Galvanometer needle will initially deflect to right first and then deflect to left

3. Galvanometer needle will deflect to right

4. Galvanometer needle will deflect to left

Q. a current carrying conductor is placed perpendicular to the uniform magnetic field. what happens to displacement of the conductor if strength of the current increases

Q. Two thick wires and two thin wires, all of the same material and same length, form a souare in three oferent ways A, B and C as shown in the figure. With correct connections shown, the magnetic field at the centre of the square is zero in case of​

Q.

how does an inductor behave in an ac circuit after the current reaches to steady state?

Q.

The unit of inductance is __.

1. Farad

2. Henry

3. Ohm
4. Volt

Q.

A coil of insulated copper wire is connected to a galvanometer. What would happen if a bar magnet is:

(i) Pushed into the coil

(ii) Withdrawn from inside the coil

(iii) Held stationary inside the coil

Q. State qualitative effect of inserting an iron core into a current carrying solenoid?

Q. Which of following circuit element stores energy in electromagnetic field?

1. inductor
2. condenser
3. variable resistor
4. capacitor

Q. Obtain an expression for the energy associated with an inductor.

Q. Find the necessary inductance. if 110 V, 10 W rating bulb is to be used with 220 V A.C source having frequency 50 Hz.

1. L=8.90 H
2. L=6.75 H
3. L=7.25 H
4. L=6.5 H