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JEE Mains · Physics · STD 12 - 2. Electric potential and capacitance
\(27\) similar drops of mercury are maintained at \(10 \,V\) each. All these spherical drops combine into a single big drop. The potential energy of the bigger drop is ....... times that of a smaller drop.
- A \(256\)
- B \(144\)
- C \(324\)
- D \(243\)
Answer & Solution
Correct Answer
(D) \(243\)
Step-by-step Solution
Detailed explanation
\((27)\left(\frac{4}{3} \pi r ^{3}\right)=\frac{4}{3} \pi R ^{3}\) \(R =3 r\) Potential energy of smaller drop : \(U _{1}=\frac{3}{5} \frac{ kq ^{2}}{ r }\) Potential energy of bigger drop : \(U =\frac{3}{5} \frac{ kQ ^{2}}{ R }\) \(U =\frac{3}{5} \frac{ k (27 q )^{2}}{ R }\)…
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