SSC
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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neither good absorbers, nor good emitters of infra-red radiation
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good absorbers, but poor emitters of infra-red radiation
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poor absorbers, but good emitters of infra-red radiation
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both good absorbers and emitters of infra-red radiation
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Detailed explanation-1: -Black matt surfaces are also very good emitters of infrared radiation once the object has become warm. On the other hand, light shiny surfaces are poor absorbers and poor emitters of infrared radiation. They’re also good reflectors. In hot countries, the houses are often painted in white or light colours.
Detailed explanation-2: -A black body absorbs all the wavelengths of light that falls on it. It absorbs light of every wavelength and do not reflect them. They not only are good absorbers but good emitters too.
Detailed explanation-3: -Dark and matt surfaces are good absorbers and emitters of infrared radiation. Light and shiny surfaces are poor absorbers and emitters of infrared radiation. Light and shiny surfaces are good reflectors of infrared radiation.
Detailed explanation-4: -Explanation: The black body is defined as a surface that absorbs all radiant energy falling on it. Black surfaces are good absorbers of heat radiations.