List of top Physics Questions on Magnetism and matter asked in NEET (UG)

The magnetic potential energy, when a magnetic bar of magnetic moment \( \vec{m} \) is placed perpendicular to the magnetic field \( \vec{B} \), is:
The magnetic moment and moment of inertia of a magnetic needle as shown are, respectively, \(1.0 \times 10^{-2} \, \text{A} \, \text{m}^2\) and \(\frac{10^{-6}}{\pi^2} \, \text{kg} \, \text{m}^2\). If it completes 10 oscillations in 10 s, the magnitude of the magnetic field is:
Problem Figure
The incorrect relation for a diamagnetic material (all the symbols carry their usual meaning and ε is a small positive number) is:
A big circular coil of 1000 turns and average radius 10 m is rotating about its horizontal diameter at 2 rad s-1. If the vertical component of earth’s magnetic field at that place is 2 × 10-5 T and electrical resistance of the coil is 12.56 Ω, then the maximum induced current in the coil will be:
A capacitor of capacitance ‘C’, is connected across an ac source of voltage V, given by V=V0sinωt The displacement current between the plates of the capacitor, would then be given by
A uniform conducting wire of length 12a and resistance ‘R’ is wound up as a current-carrying coil in the shape of, 
(i) an equilateral triangle of side ‘a’. 
(ii) a square of side ‘a’. 
The magnetic dipole moments of the coil in each case respectively are:
An iron rod of susceptibility 599 is subjected to a magnetising field of 1200 A $m^{-1}$. The permeability of the material of the rod is : $(\mu_o = 4\pi \times 10^{-7} T\,m\,A^{-1})$
At a point $A$ on the earth's surface the angle of dip. $\delta$= +25?. Ata point Bon the earth's surface the angle of dip, $\delta$ = -25?. We can interpret that:
If $\theta_1$ and $\theta_2$ be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip $\theta$ is given by :
If $\theta_1$ and $\theta_2$ be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip $\theta$ is given by :
A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in equilibrium state. The energy required to rotate it by $60^{\circ}$ is $W$. Now the torque required to keep the magnet in this new position is
A rectangular coil of length 0.12 m and width 0.1 m having 50 turns of wire is suspended vertically in a uniform magnetic field of strength 0.2 Weber/$m^2$. The coil carries a current of 2 A. If the plane of the coil is inclined at an angle of 30$^{\circ}$ with the direction of the field, the torque required to keep the coil in stable equilibrium will be
Following figures show the arrangement of bar magnets in different configurations. Each magnet has magnetic dipole moment $\overrightarrow{m}$ . Which configuration has highest net magnetic dipole moment?
A bar magnet of length '$l$' and magnetic dipole moment 'M' is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be
A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It.
A magnetic needle suspended parallel to a magnetic field requires $\sqrt 3 \,J$ of work to turn it through $60^\circ.$ The torque needed to maintain the needle in this position will be
The magnetic moment of a diamagnetic atom is
A vibration magnetometer placed in magnetic meridian has a small bar magnet. The magnet executes oscillations with a time period of $2$ sec in earth's horizontal magnetic field of $24$ microtesla. When a horizontal field of $18$ microtesla is produced opposite to the earth's field by placing a current carrying wire, the new time period of magnet will be
Electromagnets are made of soft iron because soft iron has
A bar magnet having a magnetic movement of $2 \times 10^{4} JT ^{-1}$ is free to rotate in a horizontal plane. A horizontal magnetic field $B =6 \times 10^{-4}$ T exists in the space. The work done in taking the magnet slowly from a direction parallel to the field to a direction $60^{\circ}$ from the field is :
Above Curie temperature :
Above Curie temperature :
If the magnetic dipole moment of an atom of diamagnetic material, paramagnetic material and ferromagnetic material are denoted ny $\mu_d, \mu_p$ and $\mu_f$ respectively, then
A coil in the shape of an equilateral triangle of side l is suspended between the pole pieces of a permanent magnet such that $\vec{B}$ is in plane of the coil. If due to a current i in the triangle a torque $ \tau $ acts on it, the side l of the triangle is
A diamagnetic material in a magnetic field moves