Question

Figure shows a square loop of side $1m$ and resistance $1\Omega$. The magnetic field on left side of line PQ has a magnitude $B=1.0T$. The work done in pulling the loop out of the field uniformly in $1s$ is

• A. $1J$
• B. $10J$
• C. $0.1J$
• D. $100J$

Answer 1

The correct option is A $1J$

$V=\frac{l}{t}=1m/s$

$W=Power\times Time$

$=\frac{(Blv{)}^2}{R}\times t$

$=\frac{B^2{l}^2}{Rt}=\frac{1^2\times 1^4}{1\times 1}=1J$