Physics · Electrostatics
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Two capacitors C1 (6µF) and C2 (12µF) are in series across 180 volts d.c. supply. Calculate the charges on C1 and C2
- A
720 x 10-6 C ….. 720 x 10-6 C
- B
920 x 10-6 C …. 730 x 10-6 C
- C
660 x 10-6 C …. 480 x 10-6 C
- D
440 x 10-6 C …. 770 x 10-6 C
- E
910 x 10-6 C …. 750 x 10-6 C
In a series circuit, the same charge is stored across each capacitor. The equivalent capacitance Ceq is given by the formula 1/Ceq = 1/C1 + 1/C2. For C1 = 6µF and C2 = 12µF, the equivalent capacitance Ceq is 4µF. The total charge Q can be calculated by Q = Ceq × V, where V is the voltage. Therefore, Q = 4µF × 180V = 720µC or 720 x 10-6 C. This charge is the same for both capacitors in series, making Option A correct. Other options incorrectly assume different charges for C1 and C2, which contradicts the properties of capacitors in series.
This is the correct answer because in series, both capacitors have the same charge.
This option is incorrect because it suggests different charges on C1 and C2, which is not possible in a series circuit.
This option is incorrect as the charges should be equal in a series connection.
This option is incorrect because the charges on both capacitors should be the same in a series circuit.
This option is incorrect as it violates the principle that charges are the same in a series circuit.
Tagged under Physics · Electrostatics · 2015