A thin flexible wire of length $L$ is connected to two adjacent fixed points carries a current $I$ in the clockwise direction, as shown in the figure. When system is put in a uniform magnetic field of strength $B$ going into the plane of paper, the wire takes the shape of a circle. The tension in the wire is

A rectangular loop carrying a current $i$ is situated near a long straight wire such that the wire is parallel to one of the sides of the loop and the plane of the loop is same as the left wire. If a steady current $1$ is established in the wire as shown in the (figure) the loop will -

Select the correct alternative(s): 

Two thin long parallel wires separated by a distance $b$are carrying a current $i$ ampere each. The magnitude of the force per unit length exerted by one wire on the other is

A closed loop $PQRS$ carrying a current is placed in a uniform magnetic field. if the magnetic forces on segments $PS, SR$ and $RQ$ are $F_1,{ F}_2$ and $F_3$ respectively and are in the plane of the paper and along the directions shown the directions shown, the force on the segment $QP$ is

A coil of $100$ turns is lying in a magnetic field of $1 \mathrm{T}$ as shown in the figure. A current of $1 \mathrm{A}$ is flowing in this coil. The torque acting on the coil will be

Four wires of equal length are bent in the form of four loops $P, Q, R$ and $S.$ These are suspended in a uniform magnetic field and same current is passed in them. The maximum torque will act on.