WBJEE · Physics · Capacitance
\(n\) identical droplets are charged to \(v\) volt each. If they coalesce to form a single drop, then its potential will be
- A \(n^{2 / 3} v\)
- B \(n^{1 / 3} v\)
- C \(n v\)
- D \(v / n\)
Answer & Solution
Correct Answer
(A) \(n^{2 / 3} v\)
Step-by-step Solution
Detailed explanation
\[ \begin{aligned} & \text { Hints: } n \times \frac{4}{3} \pi r^3=\frac{4}{3} \pi \mathrm{R}^3 \\ & \Rightarrow \mathrm{R}=r n^{1 / 3} \\ & \mathrm{C}_0=4 \pi \varepsilon_0 r \\ & q_0=\mathrm{C}_0 \mathrm{~V}=\left(4 \pi \varepsilon_0 r\right) \mathrm{V} \end{aligned} \]…
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