Question

Two coils $A$ and $B$ have a coefficient of mutual inductance $M=2 \, H$ . The magnetic flux passing through coil $A$ changes by $4 \, Wb$ in $10 \, s$ due to change in current in $B$ . Then

• A. Change in current in $B$ in this time interval is $0.5A$
• B. Change in current in $B$ in this time interval is $8A$
• C. The change in current in $B$ in this time interval is $2A$
• D. A change in the current of $1A$ in coil $A$ will produce a change in flux passing through $B$ by $4Wb$

Answer 1

Answer: (C)

Here, it is given that $M=2H, \, \, d\phi=4 \, Wb, \, dt=10 \, s$
As $\phi \, =M \, i \, $
$d\phi=M \, di$
Or $di=\frac{d \phi}{M}=\frac{4}{2}=2A$