An elastic circular wire of length $l$ carries a current $I$. It is placed in a uniform magnetic field $\vec{B}$ (out of the paper) such that its plane is perpendicular to the direction of $\vec{B}$. The wire will experience:

For the circuit shown in the figure,the direction and magnitude of the force on the segment $PQR$ is:

Give the expression for the force on a current-carrying conductor in a magnetic field.

$A$ fixed horizontal wire carries a current of $200\, A$. Another wire having a mass per unit length of $10^{-2}\, kg/m$ is placed below the first wire at a distance of $2\, cm$ and parallel to it. How much current must be passed through the second wire if it floats in air without any support? What should be the direction of current in it?

$A$ horizontal rod of mass $10 \, g$ and length $10 \, cm$ is placed on a smooth plane inclined at an angle of $60^\circ$ with the horizontal,with the length of the rod parallel to the edge of the inclined plane. $A$ uniform magnetic field of induction $B$ is applied vertically downwards. If the current through the rod is $1.73 \, A$,then the value of $B$ for which the rod remains stationary on the inclined plane is......$T$

Two long conductors separated by a distance $d$ carry currents $I_1$ and $I_2$ in the same direction. They exert a force $F$ on each other. Now,the current in one of them is increased to $2$ times and its direction is reversed. The distance between them is also increased to $3d$. The new value of force between them is: