Electrostatics Question 472
Question: A sphere of 4 cm radius is suspended within a hollow sphere of 6 cm radius. The inner sphere is charged to potential 3 e.s.u. and the outer sphere is earthed. The charge on the inner sphere is [MP PMT 1991]
Options:
A) 54 e.s.u.
B) $ \frac{1}{4} $ e.s.u.
C) 30 e.s.u.
D) 36 e.s.u.
Show Answer
Answer:
Correct Answer: D
Solution:
Suppose charge on inner sphere is +Q as shown. Potential on inner sphere $ V=\frac{Q}{4}-\frac{Q}{6} $
therefore $ 3=Q( \frac{1}{4}-\frac{1}{6} ) $
therefore $ Q=36e.s.u. $
