Question

A little known fact is that both Robinson Crusoe and Friday woreeyeglasses. As it so happens, Robinson Crusoe was farsighted whileFriday was nearsighted. Whose eyeglasses did they use whenever theywanted to start a fire by focusing the Sun's rays?
A) Robinson Crusoe's
B) Friday's
C) Both would work equally well.
D) Both actually worked, but Friday's was a little bitbetter.
E) Neither's worked, they were in possession ofmatches.

Answer 1

Answer:

Option A, Robinson Crusoe's

Explanation:

A far sighted person uses eyeglasses with Convex lenses. These lenses are thick at the center and thin at the edges. A farsighted person is unable to focus on nearby objects because the eye ball of a farsighted person is smaller than the normal size due to which all the refracted rays could not meet  at the retina.  

A convex lenses focuses the light at one point, this property will help in focusing the sunlight at one point for starting fire.