Which of following circular rods. (given radius r and length l ) each made of same material as whose

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10-2.Transmission of Heat

easy

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

A

$r = 2{r_0};\;l = 2{l_0}$

B

$r = 2{r_0};\;l = {l_0}$

C

$r = {r_0};\;l = {l_0}$

D

$r = {r_0};\;l = 2{l_0}$

(AIPMT-2005)

Solution

(b) $\frac{Q}{t} \propto \frac{{{r^2}}}{l}$; from the given options, option $(b)$ has higher value of $\frac{{{r^2}}}{l}$

Standard 11

Physics

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