A black body at hot temperature at 227°C radiates heat at a rate of 5 cal/$cm^{2}$s. at a temperature of 727°C the rate of heat radiated per unit area will be
50 cal/$cm^{2}$s
250 cal/$cm^{2}$s
80 cal/$cm^{2}$s
100 cal/$cm^{2}$s
Additional Questions
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Radiation emitted by a surface is directly proportional to |
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A body radiates heat at the ate of 5 cal/m2-s when its temperature is 227°C. the heat radiated by the same body when its temperature is 727°C is |
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Which one of the following constants is not related to radiation? |
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A sphere cube and a thin circular plate all made of the same material and having the same mass are initially heated to a temperature of 300°C. which of these cools fastest? |
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A black body emissive power is 81 J/m2 sec it is at 300 K another one ordinary body emissivity is 0.8 it is at 500 K then what is the emissive power of ordinary body? |
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Which one of the following constants is related to radiation? |
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