AC Circuit HW Question?

Question

An inductor has a 50.0 ohm reactance at 60.0 Hz. What is the maximum current if this inductor is connected to a 50.0 Hz source that produces a 70.0 V rms voltage?

___ A

Answer 1

Reactance = 2*pi*frequency*inductance

XL = 2pifL

Solving for inductance, L = 0.133

Now find the reactance when the frequency is 50 Hz.

Xl = 41.8 ohms

You want the maximum current: V=IZ where Z is the impedance.  If we assume that that there is no resistance or capacitance (with a capacitor reactance of 41.8 ohms and no resistance the current jumps to infinity!), impedance is equal to inductive reactance.

V=IZ

70=I(41.8)

I = 1.67 A (this is an RMS value)

If you want the maximum current, just multiply by the square root of 2.

Imax = 2.36 A

Answer 2

wow. i have no clue man. good luck