Question

An object is placed between a wall and a concave mirror . The distance between wall and mirror is 50cm . The distance between object and wall is 20cm What should be focal length of mirror if real image is formed on wall

Answer 1

Answer:

ANSWER

Given,

Focal length f=20cm

Image distance, v=50cm

from mirror formula,

f

1

=

v

1

+

u

1

⇒

−20

1

=−

50

1

+

u

1

u

1

=

50

1

−

20

1

=

50×20

20−50

=

1000

−30

u=−

3

1100cm