Question

31. A myopic person can not see objects lying beyond 2m.
The focal length and power of the
lens required to remove this defect will be
(a) Im and 0.5D (b) -2m and -0.5D
(c) 0.5m and 0.5D (d) -0.5, and 0.5D​

Answer 1

Explanation:

v=-200cm

u= infinity

1/v-1/u=1/f

here u=infinity so 1/u will be zero

1/f=-1/200

f=-200cm or -2m

so P=-0.5D