Question

Rachel has good distant vision but has a touch of presbyopia. Her near point is 0.60 m. Part A When she wears 2.0 D reading glasses, what is her near point

Answer 1

Answer:

The right answer is "0.273 m".

Explanation:

Given:

Power (P),

$\frac{1}{f} = 2D$

Near point,

u = 0.6 m

As we know,

⇒ $\frac{1}{v} -\frac{1}{u}=\frac{1}{f} = 2$

By substituting the values, we get

⇒ $\frac{1}{v} -\frac{1}{0.6} =2$

            $\frac{1}{v}=2+\frac{1}{0.6}$

            $\frac{1}{v} =\frac{1.2+1}{0.6}$

            $\frac{1}{v}=\frac{2.2}{0.6}$    

By applying cross-multiplication, we get

          $0.6=2.2 \ v$

            $v = \frac{0.6}{2.2}$

      $S_{near} = 0.273 \ m$