Electromagnetic Induction

A metal sheet is being pulled out of a region of magnetic field. IF the sheet is not magnetic:-

An inductor of inductance 0.1H and a resistor of resistance 8Ω are connected in series to a battery of emf 1.5 V through a switch. Find the initial rate of growth of current when the switch is closed (in A/s).

A copper ring of radius $\mathrm{R}=8\mathrm{c}\mathrm{m}$ and circular cross-sectional $A=2{\mathrm{m}\mathrm{m}}^2$ is in a homogeneous magnetic field whose induction is perpendicular to its plane and changes uniformly. At $t=0$ the induction is $B_0=0$ and in $\mathrm{t}=0.2\mathrm{s}$  it increases to $\mathrm{B}=2\mathrm{T}$ . The angular velocity $\omega$ at which the ring should be rotated uniformly in order not to have tensile stress in it at time instant $t_1=0.1\mathrm{s}$ is approximately: (mass of the ring $\mathrm{m}=9$ gram, Resistance $=5\mathrm{m}\mathrm{\Omega }$ , self-induction and gravity can be neglected)

Two fixed long parallel horizontal rails, a distance 1 m apart are joined at one end by a resistance 1Ω . A rod AB of negligible resistance slides towards the resistance. A magnetic field of magnitude 4T perpendicular to the plane of rails exists. Find the current flowing (in Ampere) in the resistance, at an instant when the velocity of the rod is 2 m/s.

The current in a coil of self inductance 2.0 H is increasing according to I = 2sin(t2)A. The amount of energy spent during the period when current changes from 0 to 2 A is…………J.

Match List – I with List – II.

(A) AC generator(I) Detects the presence of current in the circuit

(B) Galvanometer(II) Converts mechanical energy into electrical energy

(C) Transformer (III) Works on the principle of resonance in AC circuit

(D) Metal detector(IV) Changes an alternating voltage for smaller or greater value

Choose the correct answer from the options given below:

What is the direction of the force between two parallel current-carrying conductors?

How does the force between parallel conductors used in defining the ampere (current SI unit)?

What is the formula for the force per unit length between two parallel current-carrying conductors?

A rod of length l slides against the perpendicular wall, such that the lowest point (A) of the rod slides with a speed v on horizontal surface as shown in figure. There exist a uniform magnetic field throughout the region. Now, what is the distance of point 'P' on the rod from end 'A' such that, the induced emf across 'P' and 'A' is maximum?