The unit used to measure the power of a lens is:

The color with the longest wavelength in the visible spectrum is:

Total internal reflection occurs when light travels from a:

The splitting of white light into its component colors is called:

The working principle of an optical fiber is based on:

Which lens is used to correct hyperopia (farsightedness)?

The focal length of a plane mirror is:

Which lens is used to correct myopia (nearsightedness)?

A real image can be formed on a screen, whereas a virtual image:

The image formed by a plane mirror is:

The primary colors of light are: