A resistor of `500 Omega` and an inductance of 0.5 H are in series with an ac source which is given by `V=100sqrt(2)sin(1000t)`. The power factor of the combination is

Options

A. `1// sqrt(2)`
B. `1 // sqrt(3)`
C. `0.5`
D. `0.6`

Answer

A

Explanation

` cos phi = (R)/(Z) = (R)/(sqrt(R^(2) + (omega L)^(2))) (500)/( sqrt((500)^(2) + (1000 xx 0.5)^(2)))`
`= (1)/(sqrt(2))`