Question

Two coils $X$ and $Y$ are placed in a circuit such that a current changes by $3A$ in coil $X$ and magnetic flux changes of $1.2Wb$ occurs in $Y$. The value of mutual inductance of the coils is :

• A. $0.2H$
• B. $0.4H$
• C. $0.6H$
• D. $3.6H$

Answer 1

Answer: (B)

$0.4H$

Given, $d\varphi =Wv,M=?$
$dI=3A$
As, $\varphi =MI$
$\therefore d\varphi =MdI$
$\therefore M=\frac{d\varphi }{dI}$
$=\frac{1.2}{3}=0.4H$.