Question:
Two coils 'P' and ' $Q$ ' are separated by some distance. When a current of $3 A$ flows through coil ' $P$ ', a magnetic flux of $10^{-3} \mathrm{~Wb}$ passes through ' $\mathrm{Q}$ '. No current is passed through ' $Q$ '. When no current passes through ' $P$ ' and a current of 2 A passes through ' $Q$ ', the flux through ' $P$ ' is:
Correct Option: 1
Solution:
(1) $Q_{\text {coil }}=(N Q) \propto i$
So, $\frac{Q_{1}}{Q_{2}}=\frac{i_{1}}{i_{2}}=\frac{3}{2}$
or $Q_{2}=\frac{2}{3} Q_{1}=\frac{2}{3} \times 10^{-3}=6.67 \times 10^{-4} \mathrm{~Wb}$