Electrostatics Question 202
Question: A solid conducting sphere of radius a has a net positive charge 2Q. A conducting spherical shell of inner radius $ b $ and outer radius c is concentric with the solid sphere and has a net charge -q. The surface charge density on the inner and outer surfaces of the spherical shell will be [AMU 2002]
Options:
A) $ -\frac{2Q}{4\pi b^{2}},\frac{Q}{4\pi c^{2}} $
B) $ -\frac{Q}{4\pi b^{2}},\frac{Q}{4\pi c^{2}} $
C) $ 0,\frac{Q}{4\pi c^{2}} $
D) None of the above
Show Answer
Answer:
Correct Answer: A
Solution:
(a) Surface charge density (s) $ =\frac{\text{Charge}}{\text{Surface area}} $ So $ {\sigma _{inner}}=\frac{-2Q}{4\pi b^{2}} $ and $ {\sigma _{Outer}}=\frac{Q}{4\pi c^{2}} $
