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n identical small charged drops, each at potential V, merge to form one large spherical drop. The potential of the resulting big drop is:

1. V/n
2. Vn
3. Vn^(1/3)
4. Vn^(2/3)

Correct answer: Vn^(2/3)

Solution

Charge scales as n and radius as n^(1/3); potential = kQ/R scales as n/n^(1/3) = n^(2/3).

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