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There is a small hole in a container. At...

There is a small hole in a container. At what temperature should it be maintained in order that it emits one calorie of energy per second per `"meter"^(2)` :-

A

`10K`

B

`500K`

C

`200K`

D

`100K`

Text Solution

Verified by Experts

The correct Answer is:
D
From Stefan's law : ` DeltaQ = sigmaAT^(4)`
` implies (1"cal")/(g-m^(2)) xx (4.2J)/(cal) = 5.67 xx 10^(-8) xx 1 xx T^(4) implies T= 100K`
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