Chapter 29, Problem 6A

When you view your image in a plane mirror, how far behind the mirror is your image compared with your distance in front of the mirror?

To determine

To Examine: The distance of the image from the plane mirror when there is a person in front of a plane mirror.

Answer to Problem 6A

The image will be formed at an equal distance as it was from the plane mirror.

Explanation of Solution

Introduction:

There will be an image formed when the object is in front of the plane mirror.

The plane mirror forms an image at an equal distance from it as the object distance from the plane mirror. Thus, the person in front of the plane mirror has an image at an equal distance as the person stands in front of the plane mirror.

The distance of person in front of plane mirror = ${\mathrm{O}}_d$

The distance of image of the person behind the plane mirror = ${\mathrm{I}}_d$

The distance of the object is equal to the distance of the image as shown in the figure above.

Mathematically:

  ${\mathrm{O}}_d=I_d$

Conclusion:

The angle of incidence is equal to the angle of reflection as per the law of reflection.