Doubt from Capacitance

solved
moderate
potential
capacitance
find-work-done
pp
#1

Q no 69
Given ans option 3

1 Like
#2

#3

What about charge present on outer surfaces of plates after battery is connected?

#4

In the formula V=Q/C, Q= charge on the inner plate of capacitor.

#5

That is charge on outer plates will be undisturbed

#6

I can be wrong, but I think since it is asking the work done by the battery we should only be concerned about the charge provided by the battery, the charge is gonna flow back to the battery but it won’t affect the work done, it is going to affect the net heat/energy loss of the circuit.

#7

Current flowing in circuit is invariant along its wire.
If dq charge leaves battery and gets added in positive plate of capacitor then dq charge leaves the other capacitor plate giving negative charge.
The above must only change the charges on inner sides of plate(Cause inner sides of capacitor can only have equal and opposite charges)

Conclusion:Non facing sides charges never flow in circuit.
While solving capacitor circuits one can forget about outer side charges.
Only facing sides makes up capacitor (equal and opposite sign charge)

1 Like