Which of the following is/are not always necessary to observe a shadow?
$(a)$. Sun
$(b)$. Screen
$(c)$. Source of light
$(d)$. Opaque object

AcademicPhysicsNCERTClass 6

To observe a shadow, any source of light, an opaque object, and a screen are necessary. The sun is not necessary to observe the shadow of an object.

So, option $(a)$ is correct.

Updated on 10-Oct-2022 13:30:27