The magnetic field due to a short magnet at a point on its axis at distance $X \,cm $ from the middle point of the magnet is $200 $ $Gauss$. The magnetic field at a point on the neutral axis at a distance $ X \,cm$  from the middle of the magnet is.....$Gauss$

Force between two unit pole strength placed at a distance of one metre is

A bar magnet of length $10 \,cm$  and having the pole strength equal to $10^{-3}$ weber is kept in a magnetic field having magnetic induction $ (B)$  equal to $4\pi \times {10^{ - 3}}$ Tesla. It makes an angle of $30°$  with the direction of magnetic induction. The value of the torque acting on the magnet is

What happens to the force between magnetic poles when their pole strength and the distance between them are both doubled

Figure shows a small magnetised needle $P$ placed at a point $O$. The arrow shows the direction of its magnetic moment. The other arrows show different positions (and orientations of the magnetic moment) of another identical magnetised needle $Q$.

$(a)$ In which configuration the system is not in equilibrium?

$(b)$ In which configuration is the system in $(i)$ stable, and $(ii)$ unstable equilibrium?

$(c)$ Which configuration corresponds to the lowest potential energy among all the configurations shown?

Calculate the axial field of a finite solenoid.