Difference Between Convex Mirror and Concave Mirror

Main Difference

The main difference between the convex mirror and the concave mirror is that the convex mirror always forms a diminished image while image by concave mirror may be enlarged or diminished depending upon the position of the object.

Convex Mirror vs. Concave Mirror

A mirror is an object with smooth polished or shiny surface and reflects light in some range of wavelength to produce an image of any item. It is divided into two main types, i.e. Plane mirror and spherical mirror. A plane mirror is a mirror which has a smooth surface while spherical mirrors are mirrors with curved surfaces. A spherical mirror is further divided into two types, i.e. Convex mirror and concave mirror. A convex mirror is a mirror with reflecting surface bulges outward and it forms a diminished image while a concave mirror’s surface protrudes inward and it forms a magnified image.

Comparison Chart

Convex MirrorConcave Mirror
A spherical mirror with reflecting surface is bulging outward and used to diverge light is known as a convex mirror.A spherical mirror with reflecting surface is bulging inward and used to converge light is known as a concave mirror.
Shape
Bulging outwardBulging inward
Center of curvature
Behind the mirrorIn front of the mirror
Image
Virtual and erect imageMay form both Real and inverted image or virtual and erect image on the basis of the distance of the item from the mirror.
Size
Convex mirror forms a smaller image as compared to the original size of the object.Concave mirror may form image both smaller and larger than the size of the object on the basis of the position of object from the mirror.
Nature
It forms a diminished image.It forms a magnified image.
Projection
The image cannot be projected on the screen.The image can be projected on a screen.
Light
It diverges the beam of light.It converges the beam of light.
Example
The convex mirrors used as side mirrors of automobiles.Concave mirrors used in torch lights or reflecting telescopes etc.

What is Convex Mirror?

Convex means “rounded or curved like the outside of a circle or sphere”. A convex mirror is also recognized as a fish eye mirror or diverging mirror. If we cut a hollow sphere from the center into parts and painted its inner surface then its outer surface will act as a reflecting surface and known as a convex mirror. It diverges the light rays striking from its reflecting surface that is why it is known as a diverging mirror. It forms a diminished, virtual and erect image of the object because the center of the curvature and the focal point both are imaginary and found inside the mirror. The image will appear smaller and closer to the mirror as compared to the actual object but as the object comes close to the mirror the size of the object will keep on increasing. The Image shaped by a convex mirror cannot be projected on the screen.

Example

They are used on roads and hallways of various buildings etc. to overcome the visibility problem at blind spots.

What is Concave Mirror?

Concave means “rounded or hollowed”. The concave mirror is also known as a converging mirror because it converges the reflecting beam of light. If the cut piece of a hollow sphere is painted outward than its inner surface will act as a concave mirror. A concave mirror is used to focus the light. It may form real or virtual and small or large image on the basis of the distance of the object from the mirror. An object placed very closed to the concave mirror will form a virtual and magnified image while an object placed far away will form a real and smaller image as compared to the actual object. The image formed by a concave mirror can be projected on a screen.

Example

Concave mirrors used in torch lights and reflecting telescopes etc.

Key Differences

  1. A reflecting outer surface of a spherical mirror is known as convex mirror whereas a reflecting inner surface of a spherical mirror is known as a concave
  2. A convex mirror diverges the light while a concave mirror converges the beam of light reflecting through it.
  3. Convex mirror forms a virtual image while a concave mirror may form both virtual and real image depending upon the position of the object from the mirror.
  4. A diminished image formed by a convex mirror while a concave mirror formed a magnified image.
  5. The image formed by a convex mirror cannot be projected on a screen while image by a concave mirror can be projected on a screen.
  6. Convex mirrors are used as side mirrors of automobiles while concave mirrors are used in torch lights etc.

Comparison Video

YouTube video

Conclusion

According to the above discussions, It is concluded that Convex mirror is the diverging mirror and forms a virtual and diminished image while a concave mirror is a converging mirror which may form magnified and both virtual and real type of image depending upon the position of the object from the mirror.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss

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