Draw a ray from the object to the lens that is parallel to the principal axis. Once through the lens, the ray should pass through the principal focus. Draw a ray which passes from the object through ...

Convex and concave lenses can both be used to correct defects of vision. The most commonly occurring defects of vision are ‘short sightedness’ and ‘long sightedness’. People who are ‘short sighted’ ...

A spherical mirror is that mirror whose reflecting surface is the part of a hollow sphere of glass. Spherical mirrors are of two types: concave mirror and convex mirror. In a concave mirror reflection ...