Determine inductance from resistance and frequency?

Question

A coil has a resistance of 48.0 ohms. At a frequency of 80.0 Hz, the voltage across the coil leads the current in it by 52.3 degrees.
Determine the inductance L of the coil.

What formula would I use for this?

Answer 1

Inductive reactance XL = ωL
Phase = arctan(XL/R)
So,
XL/R = tan(phase)
XL = R*tan(phase)
L = XL/ω
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