Question

In an induction coil, the coefficient of mutual induction is $4H$. If a current of $5A$ in the primary coil is cut-off in $1/1500s$, the emf at the terminals of secondary coil will be:

• A. $10kV$
• B. $15kV$
• C. $30kV$
• D. $60kV$

Answer 1

Answer: (C)

$30kV$

As $e=M\frac{dI}{dt}$
$\therefore$ $e=4\times \frac{5}{1/1500}=30000V$
$=30kV$