Question

A person cannot see objects clearly beyond 50 cm the power of the lens to correct vision is

Answer 1

power of the lens to correct vision is -2 diopter

Answer 2

Answer: The power of the lens is -2 D

Explanation:

Given that,

The distance of the far point v = -50 cm

The distance of the object u = -∞

Using lens's formula

$\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}$

$\dfrac{1}{f}=\dfrac{1}{-50}$

$f = -50 cm$

We know that,

The reciprocal of the focal length of the lens is called power of the lens.

The power is

$P = \dfrac{100}{f}$

$P = \dfrac{100}{-50}$

$P = -2 D$

Hence, The power of the lens is -2 D.