Electromagnetic Induction - Physics PYQ | AP EAPCET

A solenoid of length \(60 \mathrm{~cm}\) with 15 turns per \(\mathrm{cm}\) and area of cross-section \(4 \times 10^{-3} \mathrm{~m}^2\) completely surrounds another co-axial solenoid of same length and area of cross-section \(2 \times 10^{-3} \mathrm{~m}^2\) with 40 turns per \(\mathrm{cm}\). Mutual inductance of the system is

An electric generator is based on

Assertion (A) It is more difficult to move a magnet into a coil with more loops.

Reason (R) This is because emf induced in each current loop resists the motion of the magnet.

Two inductors A and B when connected in parallel are equivalent to a single inductor of inductance 1.5 H and when connected in series are equivalent to a single inductor of inductance 8H. Find the difference in the inductances of A and B.

The law which states that a variation in an electric field causes magnetic field, is

An AC generator consists of a coil of 100 turns and is of cross-sectional area \(3 \mathrm{~m}^2\). It is rotating at a constant angular speed of \(60 \mathrm{~rads}^{-1}\) in a uniform magnetic field of \(0.04 \mathrm{~T}\). Resistance of the coil is \(360 \Omega\). What is the maximum power dissipation in the coil?

Assertion (A) Magnetic flux is a vector quantity.

Reason (R) Value of magnetic flux can be positive negative or zero.

The induced emf cannot be produced by

Assertion (A) When plane of coil is perpendicular to magnetic field, magnetic flux linked with the coil is minimum, but induced emf is zero.

Reason (R) \(\phi=n A B \cos \theta\) and \(e=\frac{d \phi}{d t}\)

A circular coil has 100 turns, radius 3 cm and resistance \(4 \Omega\). This coil is co-axial with a solenoid of 200 turns/\(\mathrm{cm}\) and diameter 4 cm . If the solenoid current is decreased from 2 A to zero in 0.04 s , then the current induced in the coil is

A circular loop of wire of radius 14 cm is placed in magnetic field directed perpendicular to the plane of the loop. If the field decreases at a steady rate of \(0.05 \mathrm{~Ts}^{-1}\) in some interval, then the magnitude of the emf induced in the loop is

A metallic wire loop of side $(l) 0.1 \mathrm{~m}$ and resistance of $1 \Omega$ is moved with a constant velocity in a uniform magnetic field of $2 \mathrm{Wm}^{-2}$ as shown in the figure. The magnetic field is perpendicular to the plane of the loop. The loop is connected to a network of resistors. The velocity of loop, so as to have a steady current of 1 mA in loop is

A coil of inductance $L$ is divided into 6 equal parts. All these are connected in parallel. The resultant inductance of this combination is

A horizontal telegraph wire of length 30 m spread east to west fell down freely from a height of 20 m . If the resistance of the wire is $40 \Omega$ and the horizontal component of the Earth's magnetic field at the place is $2 \times 10^{-5} \mathrm{~T}$, then the induced current when the wire reaches the ground is

(Acceleration due to gravity $=10 \mathrm{~ms}^{-2}$ )