Rate of change of torque with deflection θ is maximum for a magnet suspended freely in a uniform magnetic field of induction B when
θ = 45o
θ = 60o
θ = 0o
θ = 90o
A bar magnet has a magnetic moment of 2.5 JT-1 and is placed in a magnetic field of 0.2 parallel to antiparallel position relative to the field direction is
zero
0.5 J
2.0 J
1 J
In which type of material the magnetic susceptibility does not depend on temperature?
diamagnetic
paramagnetic
ferromagnetic
ferrite
For protecting a sensitive equipment from the external magnetic field, it should be
placed inside an aluminium can
placed inside an iron can
wrapped with insulation around it when passing current through it
surrounded with fine copper sheet
A bar magnet having a magnetic moment of 2 × 10 4 JT -1 is free to rotate in a horizontal plane. A horizontal magnetic field B = 6 × 10-4 T exists in the space. The work done in taking the magnet slowly from a direction parallel to the field to a direction 60o from the field is
0.6 J
12 J
6 J
2 J
A bar magnet is oscillating in earth’s magnetic field with a period T. What happen to its period of motion, if its mass is quadrupled?
Motion remains simple harmonic with new period = T/2
Motion remains simple harmonic with new period = 2 T
Motion remains simple harmonic with new period = 4 T
Motion remains simple harmonic and the period stays nearly constant
Due to the earth’s magnetic field, charged cosmic ray particles
can never reach the poles
can never reach the equator
require less kinetic energy to reach the equator than the poles
require greater kinetic energy to reach the equator, than the poles
Two bar magnets having same geometry with magnetic moment M and 2 M, are firstly placed in such a way that their similar poles are on the same side, then its period of oscillation is T1. Now the polarity of one of the magnets is reversed the time period of oscillations becomes T2. Then
T1 < T2
T1 > T2
T1 = T2
If a diamagnetic substance is brought near the north or the south pole of a bar magnet, it is
repelled by both the poles
repelled by the north pole and attracted by the south pole
attracted by the north pole and repelled by the south pole
attracted by both the poles
A bar magnet of magnetic moment is placed in a magnetic field of induction . The torque exerted on it is
