Question

A long straight wire is carrying current $l_1=\frac{2}{5}A$ along $+z$ direction. The $x-y$ plane contains a closed circular loop carrying and not encircling the straight wire, then the force (in newton) on the loop will be ?
$($radius of the circular loop $R=\frac{3}{4}m)$

• A. $0$
• B. $2$
• C. $-1$
• D. $1$

Answer 1

Answer: (A)

$0$

The forces at each point on the loop, in the magnetic field due to current carrying wire, balances out each other and hence net force will be zero. There will be no force along the Z axis. Forces will act along X & Y axis