Question

If an object of height 20 cm is placed in front of a concave mirror forms a real image of 10 cm height, What is the magnification?

Answer 1

Explanation:

Given : Object distance, u=−20 cm

A concave mirror forms a real magnified image only when the image to be formed is inverted i.e. m=−3

Magnification m=

u

−v

∴ −3=

−20

−v

⟹v=−60 cm

Using mirror formula :

v

1

+

u

1

=

f

1

∴

−60

1

+

−20

1

=

f

1