Question

The phase angle between the current and voltage in an L-R circuit is `30^(@)`. What is the impendance of the circuit if the resistance in the circuit is `10sqrt(3) Omega`?
A. `10 Omega`
B. `15 Omega`
C. `20 Omega`
D. `30 Omega`

Answer 1

Correct Answer - C
Power factor = `cos theta = cos 30^(@) = (sqrt3)/2`
Power factor = `R/Z`
`:. Z = R/(cos phi) = (10sqrt(3))/(sqrt(3)//2)= 20 Omega`.