List of top Physics Questions on Magnetic moment asked in JEE Main

Two identical small bar magnets each of dipole moment \( 3\sqrt{5} \text{ J/T} \) are placed at a center to center separation of 10 cm, with their axes perpendicular to each other as shown in figure. The value of magnetic field at the point P midway between the magnets is \( \alpha \times 10^{-3} \text{ T} \). The value of \( \alpha \) is _______. (\( \mu_0 = 4\pi \times 10^{-7} \text{ Tm/A} \))

An insulated wire is wound so that it forms a flat coil with \(N = 200\) turns. The radius of the innermost turn is \(r_1 = 3\) cm, and of the outermost turn \(r_2 = 6\) cm. If 20 mA current flows in it then the magnetic moment will be \(\alpha \times 10^{-2}\) A.m². The value of \(\alpha\) is ______.

A short bar magnet placed with its axis at $30^\circ$ with an external magnetic field of $800$ Gauss experiences a torque of $0.016\,\text{N m}$. The work done in moving it from most stable to most unstable position is $\alpha \times 10^{-3}\,\text{J}$. The value of $\alpha$ is ___.