Describe an activity to show that the incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.

Explanation

For this experiment take a plane mirror and stand it on a plane sheet of paper with a block. Now draw an incidence line AB. Now see in the mirror and mark the points on the paper, where you fill the line is travelling after getting reflected from the mirror. Remove the mirror and draw a perpendicular on the mirror line. Join the points to make the reflected ray. You will see that incident ray, reflected ray and normal will be in the same plane, i.e., on the sheet of paper.