Question

Determine power of accommodation of a person having normal vision of eye

Answer 1

$\huge{\mathfrak{Solution:-}}$

Light is coming from infinite distance that is why we take the object distance as infinity.

Now least distance of distinct vision is 25 cm.

So from the lens formula we get,

$\bf{\frac{1}{v}-\frac{1}{u}=\frac{1}{f}}$

Now here v is positive and u is negative.

$\bf{So,\;\frac{1}{\infty}-\frac{1}{-25}=\frac{1}{f}}$

$\bf{\implies \frac{1}{f}=\frac{1}{25}}$

$\bf{\implies f=25\;cm}$

So, the power of accommodation of eyes is, $\bf{P=\frac{100}{25}=4D}$