Electrostatics Question 798
Question: Eight drops of mercury of equal radii possessing equal charges combine to form a big drop. Then the capacitance of bigger drop compared to each individual small drop is
Options:
A) 8 times
B) 4 times
C) 2 times
D) 32 times
Show Answer
Answer:
Correct Answer: C
Solution:
[c] Volume of 8 small drops = Volume of big drop
$ 8\times \frac{4}{3}\pi R^{3}=\frac{4}{3}\pi R^{3}\Rightarrow R=2r $
As capacity is proportional to r, hence capacity becomes 2 times.