If the input voltage `V_(i)` to the circuit below is given by `V_(i)(t) = A cos(2pift)`, the output voltage is given by `V_(o)(t)=B cos(2pift+phi)`-

Which one of the following four graphs best depict the variation of `phi` vs f ?

Options

A.
B.
C.
D.

Answer

C

Explanation

Resultant of `V_(i), V_(R)`and B give `V_(i)` and angle between `V_(i) ` and B is `phi`
When f is very high
`X_(c) = (1)/(omega c) to 0 " then" V_(i) = 0 `

Resultant of `V_(i), V_(R) ` and B between B `V_(R)`

B lag behind `phi`
At higher frequency `phi` become - ve