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A material of resistivity rho is formed ...

A material of resistivity `rho` is formed in the shape of a truncated cone of altitude `h` as shown in the figure. The top end has radius a while bottom `b`. Assuming a uniform current density through any circular cross-section of the cone, the resistance between two ends is :
.

A

`(rho h)/(ab)`

B

`(rho h)/(pi ab)`

C

`(rho a)/(pi hb)`

D

`(rho b)/(pi ah)`

Text Solution

Verified by Experts

The correct Answer is:
B
For frustum of cone, `A = sqrt(A_1 A_2) = sqrt(pi a^2. pi b^2) = pi ab`
`R = (rhoh)/(A) = (rho h)/(pi ab)`.
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CP SINGH-CURRENT ELECTRICITY-Exercise
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  2. The resistance between ends will be .

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  3. A material of resistivity rho is formed in the shape of a truncated co...

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  4. Which of the following is correct regarding drift velocity.

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