A current of `4A` flows in a coil when connected to a `12V DC` source. If the same coil is connected to a `12V, 50 rad//s AC` source, a current of `2.4A` flows in the circuit. Determine the inductance of the coil. Also, find the power developed in the circuit if a`2500muF` capacitor is connected in series with the coil.

Options

A. (a), (c) are correct
B. (b), (c) are correct
C. (a), (b), (c) are correct
D. Only (b) is correct

Answer

(A),(B),(C ) are correct

Explanation

`R = (V_(dc))/(i) = (12)/(4) = 3 Omega , Z = (V_(ac))/(i) = (12)/(2.4) = 5 Omega`
use `Z = sqrt(R^(2) + omega^(2) L^(2))`
After capacitor is connected in series with the coil
`Z' = sqrt(R^(2) + (X_(L) - X_(C ))^(2))`
`:. i_("rms") = (V_(ac))/(Z') P_("ave") = i_("rms")^(2) R`