$A$ wire of length $L$ carries a current $I$. If the wire is turned into a square coil of single turn,the maximum magnitude of the torque in a given magnetic field $\overrightarrow{B}$ is

$A$ wire of length $L$ carries a current $i$. If the wire is turned into a circular coil and kept in a uniform magnetic field $B$,the maximum magnitude of torque in the given magnetic field will be

$A$ circular coil of radius $R$ and a current $I$,which can rotate about a fixed axis passing through its diameter,is initially placed such that its plane lies along the magnetic field $B$. The kinetic energy of the loop when it rotates through an angle $90^{\circ}$ is: (Assume that $I$ remains constant)

$A$ uniform current-carrying ring of mass $m$ and radius $R$ is suspended by a massless string as shown. $A$ uniform magnetic field $B_0$ exists in the region to keep the ring in a horizontal position. Determine the current $I$ in the ring.

$A$ circular coil carrying a current of $2.5 \ A$ is free to rotate about an axis in its plane perpendicular to an external magnetic field. When the coil is made to oscillate, the time period of oscillation is $T$. If the current through the coil is $10 \ A$, the time period of oscillation is:

$A$ coil having $100$ turns, area of $5 \times 10^{-3} \, m^2$, carrying current of $1 \, mA$ is placed in a uniform magnetic field of $0.20 \, T$ such that the plane of the coil is perpendicular to the magnetic field. The work done in turning the coil through $90^{\circ}$ is . . . . . . $\mu J$.