Question

Which of the following is an example of a black body radiation?

• A. The cooling of earth at night
• B. Solar radiations
• C. Heat currents from a black surface
• D. None of these

Answer 1

Answer: (A), (B)

The correct options are
A The cooling of earth at night
B Solar radiations

The Earth is heated by the flux of energy it receives from sun and cools down by emitting infrared radiations to space. So we can say that cooling of earth is example of the black body radiation.

Sun has no solid surface, any radiation that hits the Sun is scattered and absorbed until it is completely lost. This makes the Sun very close to black bodies as far as absorption is concerned and as a result it would be reasonable to suppose that it is black body radiators.

So, the radiation of sun is the black body radiation.