Question

What is the equivalent capacitance when the 2 capacitors are connected in series?

(a) Cs = C1 + C2

(b) Cs = \(\frac {1}{C_1} + \frac {1}{C_2}\)

(c) Cs = C1 + \(\frac {1}{C_2}\)

(d) Cs = \(\frac {1}{C_1}\) + C2

The question was posed to me in an interview for internship.

Origin of the question is Combination of Capacitors topic in chapter Electrostatic Potential and Capacitance of Physics – Class 12

Answer 1

Correct answer is (b) Cs = \(\frac {1}{C_1} + \frac {1}{C_2}\)

For explanation: When 2 capacitors are connected in series, the equivalent capacitance Cs is given by

Cs = \(\frac {1}{C_1} + \frac {1}{C_2}\)

When the capacitors are connected in series, the charge passing through each capacitor is the same.