Question

an object of height 10cm is placed 30cm from a concave mirror of focal length 8 cm. Find magnification?

Answer 1

Object distance u=−36 cm

Focal length of concave mirror f=−12 cm

Using mirror formula :

v

1

+

u

1

=

f

1

Or

v

1

+

−36

1

=

−12

1

⟹ v=−18 cm

Magnification

h

o

h

i

=

u

−v

Or

10

h

i

=

−10

−(−18)

⟹ h

i

=−18 cm