Question

How can you say that light travels in a straight line?​

Answer 1

Light travels in straight lines

Once light has been produced, it will keep travelling in a straight line until it hits something else.

Shadows are evidence of light travelling in straight lines. An object blocks light so that it can’t reach the surface where we see the shadow. Light fills up all of the space before it hits the object, but the whole region between the object and the surface is in shadow. Shadows don’t appear totally dark because there is still some light reaching the surface that has been reflected off other objects.

Answer 2

Answer:

By the property of RECTILINEAR PROPOGATION OF LIGHT.

Hope this helps :)