The charge on surface (ii), `q_(2)=(Q-(-3Q))/2=2Q`
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i. Hence the charges on the inner surfaces are `2Q` and `-2Q`.
ii. `V=("Charge of capacitor")/("Capacitance")=(2Q)/C`
iii. If the plates are connected, `2Q` and `-2Q` will be neutralized, so `2Q` charge will flow the from the left to the right plate.
iv. Energy lost `=` initial energy stored in capacitor
`=(2Q)^(2)/(2C)=(2Q^(2))/C`
v. If the left plate is earthed, `2Q` charge flows from the ground to the left plate. If the right plate is earthed, `2Q` charge flows from the from the ground to right plate.
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