Question

The diagram below shows an object XY in front of a plane mirror MM${}_1$.Draw the diagram, path of two rays from each point X and Y of the object to show the formation of its image.

Answer 1

By taking two random rays from both the points X and Y, we can complete the ray diagram to show image formation by following the laws of reflection, i.e., the incident ray, the normal to the plane mirror and the reflected ray, all lie on the same plane and angle of incidence is equal to angle to reflection, $\angle i=\angle r$.

First, we take two random rays from point Y. From the point of incidence, we draw two normal. Following the law of reflection ($\angle i=\angle r$) we draw the reflected rays. Extending the rays back, behind the mirror, gives the image Y${}^{\prime }$ of point Y formed at the point where they intersect. Similarly, we can obtain image X${}^{\prime }$ of point X. Joining X${}^{\prime }$ and Y${}^{\prime }$ gives the image of the object XY.