Question

Which capacitor is required in series with 12µf to get an equivalent capacitance of 4µf.

1) 6f
2) 12 µf
3) 12f
4) 6µf​

Answer 1

Answer:

4) 6µf

Equivalent capacitance (in series) = 1/capacitance1 + 1/capacitance2

1/4 = 1/12 + 1/x (x being the capacitance of the unknown capacitor)

1/4 -1/12 = 1/x

(3 - 1)/12 = 1/x

2/12 = 1/x

x = 6