An inductor `20 xx 10^(-3)` henry, a capacitor `100 mu F` and a resistor `50 Omega` are connected in series across a source of emf `V = 10 sin 314 t`.
(a) The energy dissipated in the circuit in 20 minutues is `951 J`.
(b) If resistance is removed from the circuit and the value of inductance is doubled, then the varation of current with time in the new circuit is `0.52 cos (314 t)`

Options

A. Both (a) and (b) are correct
B. Both (a) and (b) are false
C. Only (a) is corrects
D. Only (b) is correct

Answer

A

Explanation

Energy = Average power `xx` time
when resistance is removed, `cos phi = 0`
`:. phi = (pi)/(2)` , `:. I = (V_(0))/(Z) sin (omega t + phi)`