Question

Two capacitors having voltage 2F and 4F are connected in series. This combination is connected to a 100V supply, calculate the voltage across the 2F capacitor.

(a) 66.67V

(b) 33.33V

(c) 100V

(d) 0V

The question was posed to me in an internship interview.

My question is from Distribution of Voltage Across Capacitors in Series topic in portion Capacitance and Capacitors of Basic Electrical Engineering

Answer 1

The correct choice is (a) 66.67V

Explanation: Ctotal = 2*4/(2+4) = 4/3F

Q = CV = (4/3)*100 = 400/3 C.

V across 2F capacitor = Q/C = (400/3)/2 = 200/3 = 66.67F.