Q.
In the inductive circuit given in the figure, the currents rises after the switch is closed. At instant when the current is 15mA, then potential difference across the inductor will be :
Here : Current in the circuit (i)=15mA=15×10−3A
Resistance R=4000 Volt
Applied voltage in the circuit =240V
At any constant, the emf of the battery is equal to the sum of potential drop on the resistor and the emf developed in the induction coil.
Hence, E=iR+Ldtdi 240=15×10−3×4000+Ldtdi
Hence Ldtdi=Σ=240−60=180V