Question

If your eye glasses have focal length 60cm what is your near point?

Answer 1

d_n=0.25m

$D_n=1/0.25=4D$

$D_{glasses}=1/0.6=1.67D$

$\Delta D=4-1.67=2.33D$

$d=\frac{1}{\Delta D}=\frac{1}{2.33}=0.43m$

Answer d=43cm