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A body having a surface area of 50cm^2 r...

A body having a surface area of `50cm^2` radiates 300J of energy per minute at a temperature of `727^(@)C`. The emissivity of the body is
( Stefan's constant`=5.67xx10^(-8)W//m^2K^4`)

A

0.09

B

0.018

C

0.36

D

0.54

Text Solution

Verified by Experts

The correct Answer is:
B
`(dQ)/(dt)=sigma A rho T^(4)`
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NIKITA PUBLICATION-KINETIC THEORY OF GASES & RADIATION -MCQs (Stefans Law of Black Body Radiation)
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  17. A spherical black body with a radius of 12 cm radiates 450 W power at ...

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  18. A small hole is made in a metallic hollow enclosure whose walls are ma...

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