Electromagnetic Induction · Physics · AP EAPCET
MCQ (Single Correct Answer)
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 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
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 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