Question
Capacitors P, Q and R have each a capacitance C. A battery can charge the capacitor to a potential difference V. If after charging P, the battery is disconnected from it and the charged capacitor P is connected in following separate instances to Q and R (i) to Q in parallel and (ii) to R in series, then what will be potential differences between the plates of P in the two instances?
Solution
Given, three capacitors P,Q and R.
Charge acquired by the capacitor when, P is charged to a potential difference V is, Q=CV.
i) When P is connected to Q in parallel :
total capacitance -C=C1+C2 = 2C
total charge on two capacitors=q+0=q=CV
potential difference between the plates of P=
ii) When P is connected to R in series :
On such a connection, the circuit will not be completed. And hence, the sharing of charges will not take place. So, the potential will remain as V. That is, it remains unchanged.
Charge acquired by the capacitor when, P is charged to a potential difference V is, Q=CV.
i) When P is connected to Q in parallel :
total capacitance -C=C1+C2 = 2C
total charge on two capacitors=q+0=q=CV
potential difference between the plates of P=
ii) When P is connected to R in series :
On such a connection, the circuit will not be completed. And hence, the sharing of charges will not take place. So, the potential will remain as V. That is, it remains unchanged.
