Question

fill in the following blank with suitable word:
A person is short-sighted if his eyeball is too............Spectacles with a .............lens are needed. A person is long-sighted if his eyeball is too............Spectacles with a ................lens are needed. These focus light rays exactly on to the..........

Answer 1

A person is short-sighted if his eyeball is too long. Spectacles with a concave lens are needed. A person is long-sighted if his eyeball is too short. Spectacles with a convex lens are needed. These focus light rays exactly on to the retina.