Why Are Perpendicular Bisectors Used in Plane Mirror Diagrams?

[logearav]

Optics -- plane mirror

Homework Statement

Revered members,
Kindly see my attachment. I don't understand the role of dotted lines in the diagram. Actually , DA, EC and NB are perpendicular bisectors. In the first place, why should we draw perpendicular bisectors? Can't we solve the problem with incident ray and reflected ray alone? Please help, members.

Homework Equations

The Attempt at a Solution

 

[ehild]

The bisectors help you to draw the reflected ray, as it makes an angle with it equal to that of the incident ray.

ehild

 

[Villyer]

The perpendicular bisector is just the normal line to the mirror that creates the incident and reflected angles.

In this case I don't think they play a big role. This question seems more conceptual than anything.

 

[logearav]

Thanks for the replies ehild and Villyer. I got it now.

 

[rwisz]

I am happy to see your curiosity and interest in understanding the role of dotted lines in the diagram of a plane mirror. Perpendicular bisectors are drawn in this diagram to help us visualize and analyze the path of light rays as they interact with the mirror. They also help us to accurately determine the angle of incidence and angle of reflection, which are crucial in understanding the behavior of light in a plane mirror.

The incident ray and reflected ray alone may not provide enough information to accurately determine the angles and understand the behavior of light. By drawing the perpendicular bisectors, we can clearly see that the angle of incidence is equal to the angle of reflection, which is a fundamental principle in optics. This is also known as the law of reflection.

Furthermore, the perpendicular bisectors help us to understand the concept of virtual images in a plane mirror. The image formed by a plane mirror is a virtual image, which means that the light rays do not actually converge at the image point, but they appear to come from that point when reflected by the mirror. The perpendicular bisectors help us to visualize this concept by showing us that the reflected rays appear to originate from the image point.

In conclusion, the dotted lines in the diagram of a plane mirror play a crucial role in helping us understand the behavior of light and accurately determine the angles involved. I hope this explanation has helped clarify the purpose of these lines and their importance in the study of optics. Keep up the curiosity and don't hesitate to ask further questions.