Question 4
Which of the following is/are not always necessary to observe a shadow?
(a) Sun
(b) Screen
(c) Source of light
(d) Opaque object
Option (a) is the correct answer.
Shadow is formed when an opaque object falls in the path of the light. So, a source of light, an opaque object and a screen are sufficient to observe a shadow. Sun is not always necessary when there is another source of light to observe a shadow.