Question

A myopic eye can't see beyond 1m. Find the power of the lense to correct the defect.

Answer 1

u=infinity

v= -1m

lens formula:

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

$\frac{1}{f} = \frac{1}{ \infty } + ( - \frac{1}{1} ) \\ \frac{1}{f } = 0 \: - \frac{1}{1} \\ f \: = - 1m$

Power of lens:

$p = \frac{1}{f} \\ p \: = \frac{1}{ - 1 } \\ p = - 1d$