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 In an electric circuit, an inductor of inductance 0...

 In an electric circuit, an inductor of inductance 0.5 H and resistance 50Ω is connected to an alternating current source of frequency 60 Hz. Calculate the impedance of the circuit.

A.

50.0Ω

B.

450.5 Ω

C.

195.0 Ω

D.

1950.1 Ω

Correct answer is C

The impedance of a R-L circuit is given by:

Z = √(R2 + XL2) ----------- eqn(1)

where Z is the impedance,

R is the resistance, and

XL is the inductive reactance

XL = 2πfL ------------ eqn(2)

where f is the frequency

From eqn(2),

XL = 2 * π * 60 * 0.5

= 60π

Also, from eqn(1), 

Z = √(502 + (60π)2)

Z = 195.0Ω