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Which of the following circular rods, (g...

Which of the following circular rods, (given radius r and length l) each made of the same material and whose ends are maintained at the same temperature will conduct most heat ?

A

`r=2r_(0),l=2l_(0)`

B

`r=2r_(0),l=l_(0)`

C

`r=r_(0) , l=2l_(0)`

D

`r=r_(0), l=l_(0)`

Text Solution

Verified by Experts

The correct Answer is:
B
Use `R_("Heat")=(l)/(KA)=(l)/(K pir^(2))`
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