Question

If number of turns in primary and secondary coils is increased to two times each, the mutual inductance:

• A. becomes 4 times
• B. becomes 2 times
• C. becomes $\frac{1}{4}$ times
• D. remains unchanged

Answer 1

The correct option is A becomes 4 times

M = $\frac{{\mu }_0{N}_1{N}_{2}A}{l}$
$\therefore$ = M becomes 4 times.