Concepts

Class 10
Chapter 10 Class 10 - Light - Reflection and Refraction

## Uses of Convex Mirrors

We saw that, image formed by convex mirrors is

 Position of the object Position of the image Size of the image Nature of the image At infinity At the focus F, behind the mirror Highly diminished, point-sized Virtual and erect Between infinity and the pole P of the mirror Between P and F, behind the mirror Diminished Virtual and erect

So, we see that Convex Mirrors always give diminished and erect image

These mirrors are used as

### Rear View Mirror for Vehicles

They are used by drivers to see back side while driving

A convex mirror is used as a rear-view mirror because

the image provided by a convex mirror is

Erect - Hence, the image produced to the driver is not inverted, it’s right side is up.

Diminished - Hence, the image produced is much smaller than the actual size of the object. This helps in providing a wider field of view.

### Shop Security Mirrors

Shopkeepers install convex mirrors at different places on their shop

This help them keep track of thieves and shoplifters

Since these mirrors give wide field of view, a large portion of shop can be seen with the help of a single mirror

## Use of Concave Mirrors

We saw that, image formed by concave mirrors is

 Position of the object Position of the image Size of the image Nature of the image At infinity At the focus F Highly diminished, point-sized Real and inverted Beyond C Between F and C Diminished Real and inverted At C At C Same size Real and inverted Between C and F Beyond C Enlarged Real and inverted At F At infinity Highly enlarged Real and inverted Between P and F Behind the mirror Enlarged Virtual and erect

So, we see that Concave mirror gives

• Enlarged image when object is between pole and focus
• Parallel ray of light when object is placed at focus
• Converges rays of light at the focus

Now, using these results, we see the uses of Concave Mirrors

### Used as Shaving Mirrors and Makeup Mirrors

It is because when they are kept near the face, the face is within the focus of concave mirror

It produces enlarged virtual image of object

### Used by Dentist to see larger image of teeth

It is because when they are kept near the patient's teeth, the face is within the focus of concave mirror

It produces enlarged virtual image of patient's teeth so that dentist can see image of teeth easily

### Used in torches, beam lights

Light bulb is placed at focus

This produces powerful parallel beam of light. This can be seen at large distance

### Used in Solar Furnaces to Produce Heat

They have concave reflector

They concentrate sunlight and reflect it

Hence they convert solar energy into heat energy

## Questions

Question 4 Page 168 - Why do we prefer a convex mirror as a rear-view mirror in vehicles?

NCERT Question 8 - Name the type of mirror used in the following situations.