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CBSE Class 11-science Answered

What are thermal radiations? Give some of its basic characteristics.
Asked by Topperlearning User | 15 Apr, 2015, 04:45: PM
answered-by-expert Expert Answer
Thermal radiations are radiations emitted by a body (that has temperature above 0 Kelvin) on account of its temperature. Thermal radiations are also called infrared radiations as their wavelength ranges from 8 x 10-7 m to 4 x 10-4 m.

Basic characteristics of thermal radiations are:
i. They require no medium to propagate. They can travel through vacuum.

ii. They travel in straight lines with the speed of light.

iii. They do not heat the intervening medium through which they pass.

iv. Their intensity varies inversely as the square of the distance from the source.

v. They show the phenomena of interference, diffraction, reflection, refraction and polarization like light radiations.

Answered by | 15 Apr, 2015, 06:45: PM

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