Question

In displacement method we use a lens focal length f and distance between object and screen is 60 CM. Possible value for focal length is
(1) -15 cm
(2) 30 cm
(3) 12 cm
(4) 20 cm

Answer 1

Answer:

12cm

Explanation:

We know that

Max possible focal length

4×f

max

=D

f=

4

D

=

4

60=15

so f should be less than 15

so=12 cm