Electrostatics Question 91
Question: If the capacity of a spherical conductor is 1 picofarad, then its diameter, would be [Pb. PMT 1999]
Options:
A) $ 1.8\times {{10}^{-3}}m $
B) $ 18\times {{10}^{-3}}m $
C) $ 1.8\times {{10}^{-5}}m $
D) $ 18\times {{10}^{-7}}m $
Show Answer
Answer:
Correct Answer: B
Solution:
$ C=4\pi {\varepsilon _{0}}R $
$ R=\frac{C}{4\pi {\varepsilon _{0}}}=9\times 10^{9}\times {{10}^{-12}}=9\times {{10}^{-3}}m $
Diameter = 2R = 2 x 9 x 10^3 = 18 x 10^3 m
