Capacitors of values 6.0 mF and 9.0 mF are connected in series to a 30.0 V power supply.What is the resulting potential difference across the 6.0 mF capacitor?
A) 30 V
B) 18 V
C) 12 V
D) 6.0 V
E) 3.0 V

Question

Quizplus · Accepted Answer

When capacitors are connected in series, the total capacitance is given by:

1/C = 1/C1 + 1/C2

In this case, we have:

1/C = 1/6.0mF + 1/9.0mF = 0.25 mF^(-1)

Therefore, the equivalent capacitance is:

C = 4.0 mF

The potential difference across each capacitor in a series connection is the same. Therefore, the potential difference across the 6.0 mF capacitor is:

V = Q/C = (C1/C)V

where C1 is the capacitance of the capacitor in question and C is the equivalent capacitance of the circuit.

Substituting the given values, we have:

V = (6.0/4.0)V = 1.5V

Therefore, the resulting potential difference across the 6.0 mF capacitor is 18 V (Choice B).

Capacitors of Values 6