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A body at a temperature of 727^(@)C and ...

A body at a temperature of `727^(@)C` and having surface area `5 cm^(2)`, radiations `300 J` of energy each minute. The emissivity is(Given Boltzmann constant `=5.67xx10^(-8) Wm^(-2)K^(-4)`

A

`e =0.18`

B

`e=0.02`

C

`e=0.2`

D

`e=0.15`

Text Solution

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The correct Answer is:
A
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