Electrostatics Question 10
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 [MP PET 1990; MNR 1987; MP PMT 2002, 03; Pb. PET 2004; J & K CET 2005]
Options:
A) 8 times
B) 4 times
C) 2 times
D) 32 times
Show Answer
Answer:
Correct Answer: C
Solution:
Volume of 8 small drops = Volume of big drop $ 8\times \frac{4}{3}\pi r^{3}=\frac{4}{3}\pi R^{3} $
therefore R = 2r As capacity is r, hence capacity becomes 2 times.
