Question

A person needs a lens of power +2 dioptres for correcting his near vision. What is the focal length of the lens required to correct the defect?

• A. 5 m
• B. 2 m
• C. 50 cm
• D. 20 cm

Answer 1

The correct option is C 50 cm

Power = $\frac{1}{focallength}$
Focal length = $\frac{100}{2}cm$
= $50cm$