question_answer

Space between two concentric conducting spheres of radii a and \[b\left( b>a \right)\] is filled with a medium of resistivity \[\rho \]. The resistance between the two spheres will be : [JEE Main 10-4-2019 Afternoon]

A) \[\frac{\rho }{4\pi }\left( \frac{1}{a}-\frac{1}{b} \right)\]

B) \[\frac{\rho }{2\pi }\left( \frac{1}{a}-\frac{1}{b} \right)\]

C) \[\frac{\rho }{2\pi }\left( \frac{1}{a}+\frac{1}{b} \right)\]

D) \[\frac{\rho }{4\pi }\left( \frac{1}{a}+\frac{1}{b} \right)\]

Correct Answer: A

Solution :

[a]