Dispersion of light

The dispersion of light is the phenomenon of splitting of a beam of white light into its seven constituent colours when passed through a transparent medium. It was discovered by Isaac Newton in 1666. Newton discovered that light is made up of seven different colours....

Atmospheric Refraction

The atmosphere of earth consists of different layers of air. Out of these some air layers are hot which have low densities, while the others are cold which have high densities. The hot layers of air behave as optically rarer medium for light rays, whereas the cold...

Total Internal Reflection

Total internal reflection is a very interesting phenomenon which takes place when light rays pass from an optically denser medium (e.g. water, glass) into optically rarer medium (e.g. air). Now, we shall discuss the concept of total internal reflection by taking three...

Power of a lens

The power of a lens is defined as the ability of the lens to converge or diverge a beam of light falling on it. A lens is said to be of greater power if it diverges or converges a beam of light more strongly by focusing them closer to the optical centre. In other...

Magnification of a lens

The magnification of a lens may be defined as the ratio of the size (height) of the image to the size (height) of the object. The magnification of a lens is represented by the letter ‘m’. Thus,           m   =   or          m   =           Where,   h2   =   size of...