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A blackbody of surface area 1cm^(2) is p...

A blackbody of surface area `1cm^(2)` is placed inside an enclosure. The enclosure has a constant temperature `27(@)C` and the blackbody is maintained at `327^(@)C` by heating it electrically. What electric power is needed to maintain the temperature? `sigma=6.0xx10^(-8)Wm^(-2)K^(-2)` .

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The correct Answer is:
`0.73 W`
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RESONANCE ENGLISH-HEAT TRANSFER-Exercise
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  2. When q(1) joules of radiation is incident on a body if reflects and tr...

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  7. A solid copper sphere (density rho and specific heat c) of radius r a...

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  16. A solid metallic sphere of diameter 20 cm and mass 10 kg is heated to ...

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  17. Which of the law can be understood in terms of Stefan's law

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  18. A hot liquid is kept in a big room. According to Newton's law of cooli...

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  19. Three metal rods made of copper, aluminium and brass, each 20 cm long ...

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  20. A closed cubical box is made of perfectly insulating material and the ...

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