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Three metal rods of coefficient of therm...

Three metal rods of coefficient of thermal conductivities `K,2K,3K` conducts heats of `3Q, 2Q,Q` per seconds through unit area then the ratio of temperature gradients .

A

`9:3:1`

B

`9:1:1`

C

`3:1:1`

D

`1:1:1`

Text Solution

Verified by Experts

The correct Answer is:
A
`Q=(KA(Deltatheta)t)/(l)`
`((Deltatheta)/(l))prop(Q)/(K)"let"(Deltatheta)/(l)=XrArrXprop(Q)/(K)`
`X_(1) :X_(2):X_(3)=(Q_(1))/(K_(1)):(Q_(2))/(K_(2)):(Q_(3))/(K_(3))` .
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Knowledge Check

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