Two inductances connected in parallel are equivalent to a single inductance of 1.5 H, and
when connected in series are equivalent to a single inductance of 8H. The difference in their
inductance is :
A square loop of side 5 cm enters a magnetic field with 1 cms–1. The front edge enters the
magnetic field at t = 0 then which graph best depicts emf ?
The magnetic flux linked with a coil, in webers, is given by the equations Φ = 3t² + 4t + 9. Then
the magnitude of induced e.m.f. at t = 2 second will be
A rectangular coil ABCD is rotated anticlockwise with a uniform angular velocity about the axis
shown in diagram below. The axis of rotation of the coil as well as the magnetic field B are
horizontal. The induced e.m.f. in the coil would be maximum when
An inductor L, a resistance R and two identical bulbs, B1 and B2 are connected to a battery
through a switch S as shown in the figure. Which of the following statements gives the correct
description of the happenings when the switch S is closed ?
A metallic ring is attached with the wall of a room. When the north pole of a magnet is brought near to it, the induced current in the ring will be
As shown in the figure, a magnet is moved with a fast speed towards a coil at rest. Due to this
induced electromotive force, induced current and induced charge in the coil is E, I and Q
respectively. If the speed of the magnet is doubled, the incorrect statement is
Lenz’s law is a consequence of the law of conservation of:
A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field B directed into the paper AO = l and OC = 3l. Then :-
The mutual inductance between a primary and secondary circuits is 0.5 H. The resistance of the
primary and the secondary circuits are 20Ω and 5Ω respectively. To generate a current of 0.4 A
in the secondary, current in the primary must be changed at the rate of :