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A black body of mass 34.38 g and surface...

A black body of mass `34.38` g and surface area `19.2 cm^(2)` is at an initial temperature of 400 K. It is allowed to cool inside an evacuated enclose kept at constant temperature 300 K. The rate of cooling is `0.04^(@)` C/s. The specific heat of body is (Stefan's constant `sigma=5.73xx10^(-8) jm^(-2)K^(-4)`)

A

`2800 J//kg-K`

B

`2100 J//kg-K`

C

`1400 J//kg-K`

D

`1200 J//kg-K`

Text Solution

Verified by Experts

The correct Answer is:
C
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