Question

A $0.1m$ long conductor carrying a current of $50A$ is perpendicular to a magnetic field of $1.21mT$. The mechanical power to move the conductor with a speed of $1m{s}^{-1}$ is

• A. $0.25mW$
• B. $6.25mW$
• C. $0.625W$
• D. $1W$

Answer 1

The correct option is B $6.25mW$

Mechanical power required $=$ electrical power expended due to the induced emf

$=\left(Blv\right)\times I=(0.00121\times 0.1\times 1)\times 50=6.25mW$