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Question
The wavelength range of thermal radiation is
(A) from 4000 Å to 7000 Å
(B) from 7700 Å to 4 x 106 Å
(C) from 106 Å to 108 Å
(D) from 4 x 10-12 Å to 4 x 108 Å
Solution
(b) from 7700 Å to 4 x 106 Å
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