In the circuit shown in figure, initially the terminals A and P are connected together to change `4muF` capacitor. Then battery is disconnected and the terminals P and B are connected together. Then the ratio of final charge and initial charge on `4muF` capacitor is:

Options

A. `1//3`
B. `3//4`
C. `4//5`
D. `5//6`

Answer

A

Explanation

Let charge on `4 muF` capacitor when switch in position A is Q.
Charge on `4muF` capacitor after switch is shifted to position B.
`Q' = 4/(4+2)Q = (2Q)/3`
ratio `=(2Q//3)/(Q) = 2/3`