What is the net force on the rectangular coil?

Two very long straight parallel conductors of negligible cross-section carrying equal electric current of $1 \text{ mA}$ are placed one metre apart in a vacuum. The force produced per metre length is $\qquad \text{ N}$. (Given: $\mu_0 = 4\pi \times 10^{-7} \text{ T m A}^{-1}$)

The force exerted by a magnetic field on a wire having length $L$ and current $I$ is perpendicular to the wire and given as $|F| = IL|B|$. An experimental plot shows $|F|$ as a function of $L$. The plot is a straight line with a slope $S = (10 \pm 1) \times 10^{-5} \ T$. The current in the wire is $I = (15 \pm 1) \ mA$. The percentage error in $B$ is:

Wires $1$ and $2$ carrying currents $i_1$ and $i_2$ respectively are inclined at an angle $\theta$ to each other. What is the force on a small element $dl$ of wire $2$ at a distance of $r$ from wire $1$ (as shown in figure) due to the magnetic field of wire $1$?

The figure shows an equilateral triangle $ABC$ of side length '$l$' carrying currents as shown,placed in a uniform magnetic field '$B$' perpendicular to the plane of the triangle. The magnitude of the net magnetic force on the triangle is:

The magnetic force on a current-carrying wire in an external uniform magnetic field depends on: