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Two ends of a conducting rod of varying ...

Two ends of a conducting rod of varying cross-section are maintained at `200^(@)C` and `0^(@)C` respectively. In steady state:

A

Temperature difference across AB and CD are equal

B

Temperature difference across AB is greater than that of across CD

C

Temperature difference across AB is less than that of across CD

D

Temperature difference may be equal or different depending on the thermal conductivity of the rod

Text Solution

Verified by Experts

The correct Answer is:
C
Heat current will be same through every cross section
`H=(KADeltatheta)/(l)orDeltatheta=(Hl)/(KA)`
`(Deltatheta_(1))/(Deltatheta_(2))=((HX)/(KA_(1)))//(HX)/(KA_(2))=(A_(2))/(A_(1))`
Temperature difference will be more for lesser cross section
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