Question

Please answer quickly! A lens of focal length 5 cm is being used by student in the laboratory as a magnifying glass. His least distance of distinct vision is 25 cm. What magnification is the student getting?

Answer 1

Answer:

-0.25D

Explanation:

Given,

Focal Length= 5cm.

Least distance u = -25 cm

By Lens Formula,

1/v - 1/u = 1/f

=> 1/v = 1/5 - 1/25

=> 1/v =4/25.

=> v = 25/4

Now,

Magnification = v/u

=> 25/4/-25

=> -25/100

=> -1/4

=> -0.25

Therefore,

Magnification = -0.25 D

Hope it helps!