Depending on the radiating properties, a body will be black when
P = 0, x = 0 and a = 1
P= 1, T = 0 and a = 0
P = 0, x = 1 and a = 0
X = 0, a + p = 0 Where a = absorptivity, p = reflectivity, X = transmissivity.
Correct Answer :
A. P = 0, x = 0 and a = 1
Related Questions
According to Prevost theory of heat exchange
It is impossible to transfer heat from low temperature source to t high temperature source
Heat transfer by radiation requires no medium
All bodies above absolute zero emit radiation
Heat transfer in most of the cases takes place by combination of conduction, convection and radiation
The natural convection air cooled condensers are used in
Domestic refrigerators
Water coolers
Room air conditioners
All of these
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Stefan's law
Wien' law
Planck's law
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Type of surface of the body
All of these
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More or less same as for liquids and gases
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Change liquid into vapour
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At one particular temperature
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At critical temperature
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Newton Reichmann equation
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Solid ice
Melting ice
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Solids
Liquids
Gases
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Nature of the body
Kind and extent of its surface
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Coefficient of viscosity
Gravitational force
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One dimensional cases only
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P = 0, x = 0 and a = 1
P=1, x = 0, and a = 0
P = 0, T= 1, and a = 0
X = 0, a + p = 1
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Both the fluids at exit are in their hottest state
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Directly proportional to
Inversely proportional to
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Hot body to cold body
Smaller body to larger body
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