Question

A battery of e.m.f. V volt, resistors $R_1$ and $R_2$, a condenser C and switches $S_1$ and $S_2$ are connected in a circuit shown. The condenser will get fully charged to V volt when :

• A. $S_1$ and $S_2$ are both closed
• B. $S_1$ and $S_2$ are both open
• C. $S_1$ is open and $S_2$ is closed
• D. $S_1$ is closed and $S_2$ is open

Answer 1

Answer: (D)

$S_1$ is closed and $S_2$ is open

A) After the capacitor fully charged ,the current will pass through $R_2$.
Current , $i=\frac{V}{R_1+R_2}$
Voltage across C is $V_C=R_{2}i=\frac{V{R}_2}{R_1+R_2}$
B) When both switch open , no potential drop across the capacitor.
C) In this case also no potential drop across C.
D) Here the capacitor will charge through $R_1$ and the capacitor will get charged to a potential difference of V volts.