Faraday's Experiment

Q.

What are electric line of forces and its properties?

Q.

What is the dimensional formula of mutual inductance?

Q.

The phenomenon of electromagnetic induction is

1. the process of charging a body

2. the process of generating a magnetic field due to current passing through a coil

3. producing induced current in a coil due to relative motion between a magnet and the coil.

4. the process of rotating a coil of an electric motor.

Q.

In the arrangement shown in Figure, there are two coils wound on a non-conducting cylindrical rod. Initially, the key is not inserted. Then the key is inserted and later removed. Then

1. There are momentary galvanometer deflections that die out shortly; the deflections are in opposite directions.

2. There are momentary galvanometer deflections that die out shortly; the deflections are in the same direction.

3. The deflection in the galvanometer remains zero throughout.

4. There is a momentary deflection in the galvanometer but it dies out shortly and there is no effect when the key is removed.

Q.

Which of the following laws gives the direction of induced emf?

1. Lenzs law

2. Flemings left-hand rule

3. Ohms law

4. Faradays law of electromagnetic induction

Q.

The Lenzs law gives?

1. the direction of the induced current

2. the magnitude of the induced emf

3. both the magnitude and direction of the induced current

4. the magnitude of the induced current

Q.

What is difference between EMF and MMF?

Q. What is induced current?

Q.

According to Lenzs law of electromagnetic induction

1. The induced e.m.f. is not in the direction opposing the change in magnetic flux

2. The relative motion between the coil and magnet produces a change in magnetic flux

3. Only the magnet should be moved towards coil

4. Only the coil should be moved towards magnet

Q.

State Faraday's laws of electromagnetic induction.

Q.

Why the needle of galvanometer gets oppositely deflected when the bar magnet is taken inside and outside the non current carrying solenoid in Faraday experiment?

Q.

A galvanometer is used in the laboratory for detecting the null point in electrical experiments. If on passing a current of $6mA$ it produces a deflection of $2°$, its figure of merit is close to

1. $6\times {10}^{-3}A/div.$

2. $3\times {10}^{-3}A/div.$

3. $666°A/div.$

4. $333°A/div.$

Q.

According to Faradays law of electromagnetic induction

1. Eelectric field is produced by time-varying magnetic flux

2. Magnetic field is produced by time-varying electric flux

3. Magnetic field is associated with a moving charge

4. None of these

Q.

State the energy conversion and name the phenomenon which takes place when a magnet is moved inside a coil having a galvanometer at its end

1. Mechanical energy to electrical energy and electromagnetic induction

2. Electrical energy to Mechanical energy and electromagnetic induction

3. Mechanical energy to electrical energy and Mechanical effect of electric current

4. Electrical energy to Mechanical energy and Mechanical effect of electric current

Q.

Explain the Importance of the Radial Magnetic Field in a Moving Coil Galvanometer.

Q. Explain cork-screw rule.

Q.

The diagram shows a fixed coil of several turns connected to a centre zero galvanometer G and a magnet NS which can move in the direction shown in the diagram.

(a) Describe the observation in the galvanometer if (i) the magnet is moved rapidly, (ii) the magnet is kept stationary after it has moved into the coil, (iii) the magnet is then rapidly pulled out of the coil.

(b) How would the observation in (i) of part (a) change if a more powerful magnet is used?

Q.

State two factors on which the magnitude of induced e.m.f. in a coil depend.

Q.

A sinusoidal wave propagates along a string in figure (a) and (b). 'y' represents displacement of particle from the mean position. 'x' & 't' have usual meanings. Find:

1. Wavelength, frequency and speed of the wave

2. Maximum velocity and maximum acceleration of the particles

1. None of these

2. 2m, 0.25 Hz, 2 ms^-1, 1.5 mms^-1, 0.75 mms^-2

3. 4m, 0.25 Hz, 10 ms^-1, 1.5 πmms^-1, 0.75 mms^-2

4. 4m, 0.25 Hz, 1 ms^-1, 1.5 π mms^-1, 0.75 π² mms^-2

Q. The principle of electromagnetic induction was given by .

1. Oersted
2. Faraday
3. Ampere

Q.

Why induced emf is called back EMF?

Q.

Explain why an induced current must flow in such a direction so as to oppose the change producing it.

Q.

Why does it beocme more difficult to move a magnet towards a coil when the number of turns in the coil has been increased?

Q.

A plane electromagnetic wave of frequency $20MHz$ travels through space along the $X-$direction. If the electric field vector at a certain point in space is$6V{m}^{-1}$, what is the magnetic field vector at that point?

1. $2x{10}^{-8}T$

2. $\left(\frac{1}{2}\right)x{10}^{-8}T$

3. $2T$

4. $\left(\frac{1}{2}\right)T$

Q. What are electric field lines? What are their properties? What is uniform and non-uniform electric field?

Q.

Two coils A and B of insulated wire are kept close to each other. Coil A is connected to a galvanometer while coil B is connected to a battery through a key. what would happed if :

(i) a current is passed through coil B by plugging the key ?

(ii) the current is stopped by removing the plug from the key ?

Explain your answer mentioning the name of the phenomenon involved.

Q.

State and explain lenz law in details

Q.

In the following diagram, an arrow shows the motion of the coil towards the bar magnet.

The direction of the current is from A to B.

1. True

2. False

Q. How to determine the direction of magnetic dipole moment of a closed loop if current flow is clockwise direction in the loop ?

Q.

Current produced in a conductor when it moves perpendicular to magnetic field, is known as

1. Magnetic current

2. Electric current

3. Induced current

4. Conductor current