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
The work done in turning a magnet of magnetic moment M by an angle of 90o from the meridian, is n times the corresponding work done to turn it through an angle of 60o. The value of n is given by
2
1
0.5
0.25
Vertical component of earth's magnetic field is zero at a place where angle of dip is
45o
90o
0o
60o
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
In which type of material the magnetic susceptibility does not depend on temperature?
Diamagnetic
Paramagnetic
Ferromagnetic
Ferrite
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
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
The dimensions of magnetic dipole moment will be
LA
ML-1 A
ML-1 A -2
L2 A
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
According to Curie’s law, the magnetic susceptibility of a paramagnetic substance at an absolute temperature T is proportional to
T2
1/T
T
