8. (a) What do you understand by the term
ventilation? How do convection currents in
air help during ventilation?.
(b) Describe black body radiation with proper
example.
Answers
Explanation:
Ventilation is the process by which 'clean' air (normally outdoor air) is intentionally provided to a space and stale air is removed.
If an oven is on and hot, it will heat air in its vicinity. This hot air will rise and be displaced by cooler air. The heated air will cool in the area higher up and sink, and the cooler air that moved in near the oven will be heated and rise. A "circle" or cycle of convection will have been set up. by this process convection currents help in ventilation
A black body is one that absorbs all radiation incident upon it. ... A good example of a black body is a cavity with a small hole in it. Any light incident upon the hole goes into the cavity and is essentially never reflected out since it would have to undergo a very large number of reflections off walls of the cavity.
I hope it helps you