Question

If a person can’t accomodate and the glasses is +2.50 D at which distance will the person be able to see clearly?

Answer 1

The person would be able to see at distance of 40 cm if his glasses are +2.50D.

Explanation:

In order to find the length at which a person could accommodate, the formula of Diopter to focal length conversion table can be used.  In other words, if we know the power of lens, we can calculate the focal length by using the formula,

                                     $D=100 / f \text { in } \mathrm{cm}$

Where,

D - the dioptre

f - the focal length

So, by applying in this formula, in this case, $2.5=1 / f \text { or } f=100 / 2.5$, which is equal to 40 cm. Hence, the person would be able to see clearly at the distance of 40 cm.

Answer 2

The answer would be 40 centimeters.