An iron rod of susceptibility \(599\) is subjected to a magnetising field of \(1200~\text{A m}^{-1}\). The permeability of the material of the rod is:\(\left(\mu_0 = 4 \pi\times 10^{-7}~\text{T m A}^{-1}\right)\)
1. \(8.0\times 10^{-5}~\text{T m A}^{-1}\)
2. \(2.4\pi\times 10^{-5}~\text{T m A}^{-1}\)
3. \(2.4\pi\times 10^{-7}~\text{T m A}^{-1}\)
4. \(2.4\pi\times 10^{-4}~\text{T m A}^{-1}\)
A magnetic needle suspended parallel to a magnetic field requires \(\sqrt{3}~\mathrm{J}\) of work to turn it through \(60^\circ\)
1. \(3\) N-m
2. \(\sqrt{3} \) N-m
3. \(\frac32\) N-m
4. \(2\sqrt{3}\) N-m
A short bar magnet of magnet moment \(0.4\) is placed in a uniform magnetic field of \(0.16\) . The magnet is in stable equilibrium when the potential energy is:
1. \(0.064\) J
2. \(-0.064\) J
3. zero
4.\(-0.082\) J
The magnetic moment of a diamagnetic atom is:
1. 1
2. between zero and one
3. equal to zero
4. much greater than one
Two identical bar magnets are fixed with their centres at a distance d apart. A stationary charge Q is placed at P in between the gap of the two magnets at a distance D from the centre O as shown in the figure:
The force on the charge Q is in:
1. direction along OP
2. direction along PQ
3. direction perpendicular to the plane of paper
4. zero
For protecting a magnetic needle, it should be placed:
1. | In an iron box. |
2. | In a wooden box. |
3. | In a metallic box. |
4. | None of these. |
If the magnetic dipole moment of an atom of diamagnetic material, paramagnetic material and ferromagnetic material are denoted by µd, µp, and µf respectively, then:
1. µp = 0 and µf ≠ 0
2. µd ≠ 0 and µp = 0
3. µd ≠ 0 and µf ≠ 0
4. µd = 0 and µp ≠ 0
For a vibration magnetometer, the time period of the suspended bar magnet can be reduced by:
1. moving it towards the south pole
2. moving it towards the north pole
3. moving it towards the equator
4. anyone of them
Two bar magnets having the same geometry with magnetic moments M and 2M are firstly placed in such a way that if their similar poles are on the same side then their time period of oscillation is T1. Now if the polarity of one of the magnets is reversed then the time period of oscillation is T2. The relation between T1 & T2 is:
1.
2.
3.
4.
Among which of the following the magnetic susceptibility does not depend on the temperature:
1. Diamagnetism
2. Paramagnetism
3. Ferromagnetism
4. Ferrite