Question

When a coil is connected to a 100 v dc supply , the current is 2A. When the same coil is connected to a.c. source $E=100\sqrt{2}sin\omega t$ the current is 1 A. Find the inductive reactive used in the circuit.

Answer 1

In DC circuit $I=\frac{V}{R}\Rightarrow So,R=\frac{V}{I}=50\Omega$
In $AC{l}_{ms}=\frac{V_{ms}}{Z}\Rightarrow 1=\frac{100}{z}=100\Omega$
Now $Z=\sqrt{R^2+X_L^2}\Rightarrow X_L=50\sqrt{3}\Omega$