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A conductor of resistivity rho and resis...

A conductor of resistivity `rho` and resistance R, as shown in the figure, is connected across a battery of emf V. Its radius varies from a at left end to b at right end. The electric field at a point P at distance x from left end of it is

A

`(VI^2rho)/(piR[Ia+(b-a)x]^2)`

B

`(2V I^2rho)/(piR[Ia+(b+a)x]^2)`

C

`(VI^2rho)/(2piR(Ia+(b-a)x)^2)`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
A
a. `E = jrho`
`j = I/(pir^2)` [r = radius of c.s. at distance x from left end)
`r = [a+((b-a))/lx]`
Hence, `E = (VI^2rho)/(piR[al + (b-a) x]^2)`.
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