Two rods of same length and material transfer a given amount of heat in 12,s, when they are joined e

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10-2.Transmission of Heat

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Two rods of same length and material transfer a given amount of heat in $12\,s,$ when they are joined end to end. But when they are joined lengthwise, then they will transfer same heat in same conditions in .......... $\sec$

A

$24$

B

$3$

C

$1.5$

D

$48$

Solution

Let the heat transferred be $\mathrm{Q}$

When rods are joined end to end. Heat transferred by each rod

$Q=\frac{K(2 A) \Delta \theta}{l} \times 12$ $…(i)$

When rods are joined lengthwise.

$Q=\frac{K A \Delta \theta}{2 l} t$ $…(ii)$

From equation $(\mathrm{i})$ and $(\mathrm{ii})$ we get $=48 \mathrm{s}$

Standard 11

Physics

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