Question

The shape of spot light produced when bright sunshine passes perpendicular through a hole of very small size, is:
(A) Square because hole is square
(B) Round because it is an image of the sun
(C) Round with a small penumbra around it
(D) Square with a small penumbra

Answer 1

Hint We should know that when the light rays travel in the straight line, then if an object obstructs the rays from the source of the light, and if the unobstructed rays fall on any other surface then there is the formation of the shadow. The portion of the surface which will not receive the light from the light source is known as its shadow.

Complete step by step answer
We should know that the spots are often oval, rather than round. That is because the sunlight is hitting the ground at an angle and the round sun images are stretching out to make ovals.
It is perpendicular to the sun’s rays, and the spots should become round.
So, we can say that the shape of spot light produced when bright sunshine passes perpendicularly through a hole of very small size, is round because it is an image of the sun.

Hence the correct answer is option B.

Note We should know that umbra and penumbra are the different parts of the shadow. The umbra is defined as the innermost and the darkest part of the shadow. This is the place where the light source is completely blocked by the obstructing body.
The penumbra is defined as the region in the shadow where the light source is obstructed by the obstructing body.