Question

A doctor has prescribed a corrective lens of power $+1.5D$. Find the focal length of the lens. Is the prescribed lens diverging or converging?

Answer 1

Power of lens $p=+1.5D$

$p=\frac{1}{f}$

$1.5=\frac{1}{f}$

$f=\frac{1}{1.5}m$

$f=\frac{10}{15}m$

$f=\frac{2}{3}m=0.67m$

Focal length of the lens is $+0.67m$.

The prescribed lens is converging in nature.