Please answer the following curcuit question....thank you?

Question

A 60 mH inductor passes a current of 200mA when connected to a 400 Hz supply. Calculate the supply voltage.

Show work

Answer 1

This is an AC electric circuit problem.

Remember Ohm's law: V = I R
(V is voltage, I is current, R is resistance)

There is an analogous law for AC circuits: V = I Z
Z is "impedance", which is a property that applies to AC circuits.

For an inductor, Z = j omega L
(j is sqrt(-1), omega is frequency in radians/sec, L is impedance in Henrys)

We are not interested in the phase for this problem, so we can just use the magnitude of Z. (ignore the j)

omega = 400 * 2 * pi = 2513.3 rad/s
Z = omega L = (2513.3 rad/s) * (0.06 Henrys) = 150.8 ohm

V = I Z = (0.2 Ampere) * (150.8 ohm)

V = 30.16 Volts

Answer 2

v = L(di/dt)
t=1/f=1/400Hz=2.5mSc
L=60mH
di=200mA

v = (60mH)(200mA)/(2.5ms) = 4.8V

4.8V is your answer.