Question

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

• A. $\frac{i B L}{\pi}$
• B. $i B L \pi$
• C. $2 i B L$
• D. Zero

Answer 1

Answer: (C)

$|\vec{I}|=2 L$
Now, using $F=$ ilB
$=i(2 L) B$