Physics (Essay) Paper 2 WASSCE (PC), 2022

Question 7

 

(a)        What is a perfect blackbody?
(b)        Give one practical example of a blackbody.

Observation

 

The expected response:
(a)   Definition of a perfect blackbody               

A body that absorbs all incident radiations falling on it without reflecting or transmitting any.
OR

A body that absorbs completely radiations of all wavelengths falling on it.


(b)       Practical examples of a blackbody
-           A tiny deep hole (inside a cavity)      
-           The sun
-           The earth.