For the circuit shown in figure, which of the following statements is true ?

Options

A. (a) With `S_1` closed `V_1=15V`, `V_2=20V`
B. (b) With `S_3` closed, `V_1=V_2=25V`
C. (c) With `S_1` and `S_2` closed, `V_1=V_2=0`
D. (d) With `S_1` and `S_3` closed, `V_1=30V`, `V_2=20V`

Answer

D

Explanation

With the cloisng of switch `S_3` and `S_1` the negative charge on `C_2` will attract the poistive charge on `C_2` thereby maintaining the negative charge on `C_1`. The negative charge on `C_1` will attract the poistive charge on `C_1`. No transfer of charge will take place. Therefore p.d across `C_1` and `C_2` will be 30 V and 20V.