Question

The adjoining figure shows an `AC` circuit with resistane `R`, inductance `L` and source voltage `V_S`. Then

A. the source voltage `V_s=72.8V`
B. the plane angle between current and source voltage is `tan^-1(7/2)`
C. both a and b are correct
D. both a and b are wrong

Answer 1

Correct Answer - A
`V_(S)=sqrt(V_R^2+V_L^2)`
`sqrt((70)^2+(20)^2)=72.8V`
`tanphi=X_L/r=V_L/V_R=20/70=2/7`