Question

A sphere of radius 0.03m is suspended within a hollow sphere of radius 0.05m. If the inner sphere is charged to a potential of 1500 volt and outer sphere is earthed. Find the capacitance and the charge of the inner sphere.

Answer 1

Explanation:

Potential on outer surface:

0.05KQ1+0.05KQ2=0

⇒Q1=−Q2

Potential on inner surface:

0.03KQ1−0.05KQ2=1500

Q1=2×9×1091500×15×10−2

=12.5×10−9C

C=VQ=150012.5×10−9=8.33×10−12F