The far point of a myopic person is 40 , cm. | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) myopic person suffers from myopia (nearsightedness),which is corrected using a concave lens.For a myopic person,the far point is at $40 \, cm$. To

Vedclass · Accepted Answer

Concave lens,$f = -40 \, cm, P = -2.5 \, D$

Vedclass · Answer

(A) myopic person suffers from myopia (nearsightedness),which is corrected using a concave lens.For a myopic person,the far point is at $40 \, cm$. To see distant objects (at infinity) clearly,the lens must form a virtual image of the object at the person's far point.Given: Object distance $u = \infty$,Image distance $v = -40 \, cm = -0.4 \, m$.Using the lens formula: $\frac{1}{f} = \frac{1}{v} - \frac{1}{u}$.Substituting the values: $\frac{1}{f} = \frac{1}{-0.4} - \frac{1}{\infty} = -2.5 \, m^{-1}$.Thus,the focal length $f = -0.4 \, m = -40 \, cm$.The power of the lens $P = \frac{1}{f 	ext{ (in meters)}} = \frac{1}{-0.4} = -2.5 \, D$.Therefore,a concave lens of focal length $40 \, cm$ and power $-2.5 \, D$ is required.

The far point of a myopic person is $40 \, cm$. What type of lens should they wear to see distant objects clearly? Calculate the focal length and the power of the lens they should use.

Similar Questions

What is the phenomenon of splitting of white light into its seven constituent colors called?

To correct astigmatism,we use a cylindrical lens.

What is meant by accommodation of the eye?

Which colour of white light suffers $(i)$ least deviation and $(ii)$ maximum deviation when a beam of white light passes through a glass prism?

Which of the following is not a secondary color?

Vedclass Test Series

Exam Paper Generator

Online Exam Module