The force on a current-carrying loop (radius $= R$) in a uniform magnetic field $(B)$,which is at an angle $30^{\circ}$ with the normal,will be:

Two very long straight parallel conductors of negligible cross-section carrying equal electric current of $1 \text{ mA}$ are placed one metre apart in a vacuum. The force produced per metre length is $\qquad \text{ N}$. (Given: $\mu_0 = 4\pi \times 10^{-7} \text{ T m A}^{-1}$)

$A$ straight wire carrying a current $i_1 \, A$ runs along the axis of a circular loop carrying a current $i_2 \, A$. The force of interaction between the two current-carrying conductors is

As shown in the figure, a metallic rod of linear density $0.45\,kg\,m^{-1}$ is lying horizontally on a smooth inclined plane which makes an angle of $45^{\circ}$ with the horizontal. The minimum current flowing in the rod required to keep it stationary, when a $0.15\,T$ magnetic field is acting on it in the vertical upward direction, will be $....A$ $\{$Use $g=10\,m/s^2\}$

$A$ circular coil of wire carries a current. $PQ$ is a part of a very long wire carrying a current and passing close to the circular coil. If the directions of currents are those shown in the figure,what is the direction of the force acting on $PQ$?

Two long straight wires are arranged parallel to each other and are kept $20$ cm apart in vacuum. They carry currents of $2$ $A$ and $4$ $A$ respectively in the same direction. What will be the magnetic force on a length of $10$ cm of either wire? $(\mu_0 = 4\pi \times 10^{-7} \text{ SI units})$