Q 12-02-015NEETNEET 2021Top questionMedium
Twenty seven drops of same size are charged at $220$ V each. They combine to form a bigger drop. Calculate the potential of the bigger drop.
Answer: (A) $1980$ V
Concept. Volume conserved ($R = 3r$), charge adds ($27q$).
Step 1. Potential. $\dfrac{27kq}{3r} = 9 \times 220 = 1980$ V.
Answer. $1980$ V (Option A).
Solution by Sreeraj P, M.Sc Physics