This problem involves the redistribution of charge and the consequent loss of energy when two capacitors are connected, a concept detailed in NCERT Example 2.10.
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Initial State: A capacitor C1=2μF is charged to a potential V. The initial stored energy is:
Ui=21C1V2
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Final State: The switch is turned to position 2, connecting C1 in parallel with an uncharged capacitor C2 (implied to be 8μF based on the answer option). Charge flows until they reach a common potential V′.
V′=Total CapacityTotal Charge=C1+C2C1V
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Final Energy: The total energy stored in the combination is:
Uf=21(C1+C2)(V′)2=21(C1+C2)(C1+C2C1V)2=21(C1+C2)C12V2
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Energy Loss:
ΔU=Ui−Uf=21C1V2−21(C1+C2)C12V2=21C1V2(1−C1+C2C1)
ΔU=Ui(C1+C2C2)
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Percentage Dissipated:
% Loss=UiΔU×100=(C1+C2C2)×100
Substituting C1=2μF and C2=8μF:
% Loss=2+88×100=108×100=80%
This loss appears as heat and electromagnetic radiation [NCERT Class 12, Sec 2.15, Example 2.10].