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A sperical shell , made of material of e...

A sperical shell , made of material of electrical conductivity `10^9//pi(Omegam)^(-1)`, has thickness t = 2 mm and radius R = 10 cm. In an arrangement, its inside surface is kept at a lower potential than its outside surface. The resistance offered by the shell is equal to

A

`5pi xx 10^(-12) Omega`

B

`2.5 xx 10^(-11)Omega`

C

`5 xx 10^(-12)Omega`

D

`5 xx 10^(-11)Omega`

Text Solution

Verified by Experts

The correct Answer is:
D
d. `R = 1/sigma xx t/(4piR^2)`
Using values ` R = 5 xx 10^(-11) Omega` .
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