Concave or diverging lens is needed correct the vision of a nearsighted person whose far point is 30.0 cm
Solution:
Nearsighted person will not be able to see the distant objects clearly
Now, we want the near sighted person to see the distant objects clearly
The lens equation is given as:
[tex]P = \frac{1}{d_o} + \frac{1}{d_i}[/tex]
For distant vision, [tex]d_0 = \infty[/tex]
[tex]d_i = image\ distance\\\\d_0 = lens\ to\ retina\ distance[/tex]
The image of 30 cm from eye will be 28.5 cm to left of spectacle lens
Therefore,
[tex]d_i = -28.5\ cm = 0.285\ meter[/tex]
From lens equation,
[tex]P = \frac{1}{ \infty } + \frac{1}{-0.285\ meter}\\\\P = 0 - 3.51 \\\\P = -3.51\ diopter[/tex]
The negative power -3.51 D denotes that a concave or diverging lens is needed
