216 identical spherical drops each having a positive charge of
\[
10\,\text{nC}
\]
combine to form a big spherical drop. If the radius of each small drop is
\[
3\,\text{mm},
\]
then the capacitance and electric potential of the big drop are respectively
Show Hint
When \(n\) identical drops combine:
\[
R=n^{1/3}r,
\qquad
Q=nq.
\]
For a spherical conductor:
\[
C=4\pi\varepsilon_0R,
\qquad
V=\frac{Q}{C}.
\]
The potential increases as \(n^{2/3}\).