AP EAMCET2013PhysicsRay Optics
A microscope consists of an objective of focal length 1.9 ~cm and eye piece of focal length 5 ~cm . The two lenses are kept at a distance of 10.5 ~cm . If the image is to be formed at the least distance of distinct vision, the distance at which the object is to be placed before the objective is (least distance of distinct vision is 25 ~cm )
Options
- A6.2 ~cm
- B2.7 ~cm
- C21.0 ~cm
- D4.17 ~cm
Correct answer
B. 2.7 ~cm
Step-by-step solution
For eye piece array cc & V_e=-25 ~cm , f_e=5 ~cm & 1 -25 - 1 u_e = 1 5 & u_e=- 25 6 ~cm & v₀=L- |u_e |=10.5- 25 6 = 38 6 ~cm array For objective array ll & 1 v₀ - 1 u₀ = 1 f₀ & 1 38 / 6 - 1 u₀ = 1 1.9 & 1 u₀ = 6 38 - 1 1.9 & u₀=2.7 ~cm array