Physics · Electrostatics | MDCAT MCQ

Question

Two capacitors C1 ( 12 uf ) and C2 (24 uf) are in series connected across a 360 volts d.c. supply. Calculate the charges on C1 and C2 respectively.

Options

A
2880 x 10-6 C , 2880 x 10-6
B
4770 x 10-6 C, 4770 x 10-6
C
5810 x 10-6 , 6610 x 10-6
D
7170 x 10-6 , 8140 x 10-6
E
9090 x 10-6 , 8880 x 10-6

Explanation

Charge throughout the circuit is the same so either the answer is A or B, as only these options have the same charge throughout.Q=CVCapacitance in series can be calculated as:1/C=1/C1 + 1/C21/C=1/12 + 1/241/C=2+1/241/C=⅛C=8 microfarads.->Q=CVQ=(8x10^-6)(360) Q=2880 x 10-6 C

This is correct. The charge on capacitors in series is the same, and the total capacitance in series is calculated correctly, leading to this charge.

Incorrect. The calculation of total capacitance is incorrect, leading to an incorrect charge value.

Incorrect. This option provides different charges for the capacitors, which is not possible in series configuration.

Incorrect. The charges are different, which is impossible for capacitors in series.

Incorrect. The charges provided are inconsistent with the principle that capacitors in series have the same charge.