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प्रश्न
Explain briefly the process of heat transfer by radiation.
उत्तर
RADIATION. “The transfer of heat energy from a hot body to cold body directly, without heating the medium between two bodies is called RADIATION.”
The radiant heat or thermal radiation is of the form of ELECTROMAGNETIC WAVES. These waves can travel even in vacuum in all directions in straight line with the speed of light. They do not heat the medium through which they pass. Heat radiations are also called INFRA-RED RADIATIONS because the wavelength of heat radiations is longer than that of visible light. These radiations can cause heating effect only if they are absorbed by some material
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संबंधित प्रश्न
No medium is required for transfer of heat by the process of ______.
Write true or false for a given statement.
On touching a lump of ice, we feel cold because some heat passes from our body to the ice.
Write true or false for a given statement.
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Black surfaces are the poor absorbers of heat radiations.
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State the direction of heat transfer by way of convection.
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