Thin Lens And Lens Maker Equations Video Lessons

Concept

# Problem: Suppose the distance from the lens system of the eye (cornea + lens) to the retina is 18 mm. Suppose that the eye is farsighted: the person cannot see clearly objects that are closer than 1.0 m. Find the power of the contact lens you would prescribe so that objects as close as 20.0 cm can be seen cleariy.

###### FREE Expert Solution

Lens equation:
$\overline{)\frac{\mathbf{1}}{{\mathbit{s}}_{\mathbit{o}}}{\mathbf{+}}\frac{\mathbf{1}}{{\mathbit{s}}_{\mathbit{i}}}{\mathbf{=}}\frac{\mathbf{1}}{\mathbit{f}}}$

Power of a lens:

$\overline{){\mathbf{D}}{\mathbf{=}}\frac{\mathbf{1}}{\mathbf{f}}}$

Object distance, so = 20 cm(1m/100cm) = 0.2 m

91% (290 ratings)
###### Problem Details

Suppose the distance from the lens system of the eye (cornea + lens) to the retina is 18 mm.

Suppose that the eye is farsighted: the person cannot see clearly objects that are closer than 1.0 m. Find the power of the contact lens you would prescribe so that objects as close as 20.0 cm can be seen cleariy.