NCERT Question 7 - Chapter 10 Class 10 - Light - Reflection and Refraction

We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.

Answer

A concave mirror produces an erect image only when 

the object is placed between pole and focus.

Now,

Distance between pole and focus = Focal length

                                                      = 15cm

Hence, the object can be placed at a distance of less than 15 cm in front of the mirror.

Range of distance of object = less than 15cm

Now,

The nature of the image formed when object is placed between pole and focus of concave mirror is

Virtual, erect and enlarged