(A) zero
(B) 3.0 V
(C) 1.5 V
(D) 0.75 V
Tag: Physics Mcq Questions and Answers
The current passing through a choke coil of 5 H is decreasing at the rate of 2 A/s. The emf developed across the coil is:
(A) 10 V
(B) -10 V
(C) 2.5 V
(D) -2.5 V
An ideal transfer is used to step up an alternating emf of 220 V to 4.4 kV to transmit 6.6 kW of power. The current rating of the secondary is:
(A) 30 A
(B) 3 A
(C) 1.5 A
(D) 1 A
To induce an emf in a coil, the linking magnetic flux:
(A) must decrease
(B) must increase
(C) must remain constant
(D) can either increase or decrease
The direction of induced emf during electromagnetic induction is given by:
(A) Faraday’s law
(B) Lenz’s law
(C) Maxwell’s law
(D) Ampere’s law
The self-inductance of a coil is 5 h. A current of 1 A changes to 2 A within 5 s through the coil. The value of induced emf will be:
(A) 10 V
(B) 0.1 V
(C) 1.0 V
(D) 100 V
When the current in a coil changes from 2 A to 4 A in 0.05 s, and emf of 8V is induced in the coil. The coefficient of self-inductin of the coil is:
(A) 0.1 H
(B) 0.2 H
(C) 0.4 H
(D) 0.8 H
Faraday’s law of electromagnetic induction is related to the:
(A) law of conservation of charge
(B) law of conservation of energy
(C) third law of motion
(D) law of conservation of angular momentum