The dimensions of magnetic dipole moment will be
LA
ML-1 A
ML-1 A -2
L2 A
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
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 of magnetic moment is placed in a magnetic field of induction . The torque exerted on it is
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
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
Vertical component of earth's magnetic field is zero at a place where angle of dip is
45o
90o
0o
60o
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 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
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
