A voltage of 100V RMS at 50Hz is connected to a 45ohm resistor in parallel with an inductance of 150mH. Calculate the inductor current.This is a question i have to work out, I just don't understand the formula for working out current through an inductor Vl di/dt, any help??
Steady state inductor current VL/XL 200Vrms/[(6.28)*(50)*(.150)] Ohms 4.25 Amps
Inductive reactance magnitude under ac is X ω.L 2.π.50 100.π ohms With 100 v applied this would give a current in the inductor of i 100/X 1/π amps. Note: When V is sinusoidal (i.e. ac) V L.di/dt becomes v.sin(ωt) L.di/dt therefore di/dt V/L (v/L)sin(ωt) so that i -v/(ωL) s(ωt) or in terms of magnitudes i V/(ωL) ωL is the reactance of L. The resistor's current is irrelevant here.
