Dispersion of White Light

When white light or sunlight was passed through a prism in a dark room, it was observed that the white light formed a spectrum of light consisting of different colours (Red, orange, yellow, green, blue, indigo & violet) on a screen.

As the light passes through the prisms, it is deviated and the spectrum is spread out on the screen. Observation shows that Red light is the least deviated and violet light is the most deviated.