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
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
The angle of dip is 90o at
Earth's magnetic poles
Equator
Both (1) and (2 )
None of these
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 is placed with its north pole pointing earth’s north. The points of zero magnetic field will be which direction from the centre of the magnet?
North and South
East and West
North-east and South-west
North-east and South-east
Nickel shows ferromagnetic property at room temperature. If the temperature is increased beyond Curie temperature, then it will show
Paramagnetism
Anti-ferromagnetism
No magnetic property
Diamagnetism
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
A bar magnet has a magnetic moment of 2.5 JT-1 and is placed in a magnetic field of 0.2 parallel to anti parallel position relative to the field direction is
Zero
0.5 J
2.0 J
1 J
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
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
