7) In an L-R-C series circuit the current is given by i = I cos wt. The voltage amplitudes for the resistor, inductor, and capacitor are VR , V,, and V. (a) The instantaneous power into the resistor is pp = V. I cos wt = 1/2V I(1 + cos 2wt). What does this expression give for the average power into the resistor? (b) The instantaneous power into the inductor is p, = -V,I sin wt cos wt = - 1/2V, I sin 2wt. What does this expression give for the average power into the inductor? (c) The instantaneous power into the capacitor is p. =V. I sin wt cos wt = 1/2V I sin 2wt. What does this expression give for the average power into the capacitor? Answer: (a) ( 1/2) VPI (b) 0 (c) 0 Prav = T T OL PRdt Rav = J PLdt Pcav = S Pc dt D T T T