Question

Due to the presence of the current $I_1$ at the origin

• A. The forces on $AB$ and $DC$ are zero
• B. The forces on $AD$ and $BC$ are zero
• C. The magnitude of the net force on the loop is given by $\frac{\mu_{o}II_{1}}{4\pi}\left[2\left(b-a\right)+\frac{\pi}{3}\left(a+b\right)\right]$
• D. The magnitude of the net force on the loop is given by $\frac{\mu_{o}II_{1}}{24ab}\left(b-a\right)$

Answer 1

Answer: (B)

The forces on $AD$ and $BC$ are zero

Answer 2

The forces on AD and BC are zero because magnetic field due to a straight wire on AD and BC is parallel to elementary length of the loop.