If a current is passed through a spring,then the spring will:

What is the net force on the square coil?

The magnetic force between the wires as shown in the figure is:

$A$ 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 $PQ$?

$A$ wire carrying a current $i$ is placed in a uniform magnetic field in the form of the curve $y = a \sin \left( \frac{\pi x}{L} \right)$,$0 \leq x \leq 2L$. The force acting on the wire is

$A$ semicircular ring of radius $R$ carrying current $i$ is placed in a uniform magnetic field of intensity $B$ such that the plane of the wire is perpendicular to the magnetic field,as shown in the figure. The net force acting on the ring is