Question

Two coils have a mutual inductance of $0.005H$. The current changes in the first coil according to equation $I=I_0\sin \omega t$, where $I_0=10A$ and $\omega =100\pi$ $rad/s$. The maximum value of emf (in volt) in the second coil is

• A. $2\pi$
• B. $5\pi$
• C. $\pi$
• D. $4\pi$

Answer 1

Answer: (B)

$5\pi$

$\frac{dI}{dt}=I_0\omega \cos \omega t$

$e=M\frac{dI}{dt}=I_0\omega \cos \omega t$

$\therefore$ $e_{max}=M{I}_0\omega$

$=0.005\times 10\times 100\pi$

$=\left(5\pi \right)V$