In a `L-R` circuit, the value of `L` is `(0.4/(pi))` henry and the value of `R` is `30` ohm. If in the circuit, an alternating e.m.f of `200` vol at `50` cycles per sec is connected, the impendence of the circuit will be

Options

A. 50 ohm
B. 60 ohm
C. 2 amphere
D. 4 amphere

Answer

A,D

Explanation

Here
`X_(L) = omega L = 2 pi fL = 2 pi xx 50 xx (0.4)/(pi) = 40 Omega`
`R = 30 Omega`
` :. Z = sqrt(R^(2) + X_(L)^(2)) = sqrt(30^(2) + 40^(2)) = 50 Omega`
`I_("rms") = (V_("rms"))/(Z) = (200)/(50) = 4A`