The image seen in a plane mirror is located
A. at the surface of the mirror
B. behind the mirror
C. in front of the mirror
D. at the position of the object
The correct answer and explanation is :
Correct Answer: B. Behind the mirror
Explanation:
A plane mirror forms a virtual image of an object placed in front of it. The image appears to be located behind the mirror at the same distance as the object is in front of the mirror. This phenomenon can be understood using the laws of reflection and the principle of reversibility of light.
1. Laws of Reflection:
The reflection of light follows two basic rules:
- The angle of incidence is equal to the angle of reflection.
- The incident ray, the reflected ray, and the normal to the mirror’s surface all lie in the same plane.
When light rays from an object strike the mirror, they reflect off the surface according to these laws. However, our brain perceives light as traveling in straight lines. Since the reflected rays appear to originate from a point behind the mirror, the brain interprets the image as being located there.
2. Image Characteristics in a Plane Mirror:
- Virtual: The image cannot be projected onto a screen because no actual light converges at the image location.
- Erect: The image appears upright, maintaining the same orientation as the object.
- Laterally Inverted: The image appears reversed from left to right.
- Same Size: The image is of the same size as the object.
- Equidistant: The image is as far behind the mirror as the object is in front of it.
This principle is why when you look at yourself in a mirror, you seem to see yourself behind the glass rather than on its surface or in front of it.