Question

A circuit having a resistance, an inductance, and a capacitance in series is connected to a 110- v ac line.for the circuit R = 0.0 xl = 28 and xc = 16 compute (a) the impedance of the circuit (b) the current (c) the phase angle between the current and the supply volt (d) the power factor of the circuit

Answer 1

Part A)

Impedance of the circuit is given by

$z = \sqrt{(x_L - x_c)^2 + R^2}$

$z = \sqrt{(28 - 16)^2 + 0^2}$

$z = 12 ohm$

Part b)

Now in order to find the current we will use ohm's law

$V = i*z$

$110 = i * 12$

$i = 9.17 A$

Part c)

Phase angle is defined as

$\phi = tan^{-1}\frac{x_L - x_C}{R}$

$\phi = tan^{-1}\frac{12}{0}$

$\phi = 90 degree$

Part d)

now power factor is defined as

$cos\phi = \frac{R}{Z}$

$Power factor = 0$