Question

Which of the following is/are not always necessary to observe a shadow?

(a) Sun

(b) Screen

(c) Source of light

(d) Opaque object

Answer 1

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.