Two long straight parallel conductors separated by a distance of $0.5\,m$ carry currents of $5\,A$ and $8\,A$ in the same direction. The force per unit length experienced by each other is

$A$ square current-carrying loop is suspended in a uniform magnetic field acting in the plane of the loop. If the force on one arm of the loop is $\overrightarrow{F}$,the net force on the remaining three arms of the loop is

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

$A$ straight wire of mass $0.2 \,kg$ and length $1.5 \,m$ carries a current of $2 \,A$, as shown in the figure. It is suspended in mid-air by a uniform magnetic field $B$ pointing into the plane of the paper. Calculate the magnitude of the magnetic field. (Ignore Earth's magnetic field and assume $g = 10 \,m/s^2$) (in $\,T$)

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

Two long wires carrying currents $I_1$ and $I_2$ are arranged as shown in the figure. The wire carrying current $I_1$ is along the $x$-axis. The other wire carrying current $I_2$ is parallel to the $y$-axis,passing through the point $(0, 0, d)$. Find the magnetic force exerted on a segment of length $dl$ of the second wire at the point $O_2(0, 0, d)$ due to the wire carrying current $I_1$.