Question

Give reason why a band of colours are produced when white light falls on a prism for class 8

Answer 1

Newton did an experiment with a prism and icident a white light on it...the difference between the air and glass densities is in the ratio of 1:2. Let n1 be the medium of air and n2 be the medium of glass. The white light is refracted and is splitted into 7 colour ROYGBIV Red Orange Yellow Green Blue Indigo Violet. It happens because of dispersion of light Ray.This dispersion of light happens as each color light has different velocity and and different deviation value. Due to this refracted rays occur as light is refracted on different angles...Hope this helps you

Answer 2

The band of colors depends upon the refraction of light and dispersion.

• The refraction of light means the bending of light. As we know that white light consists of seven colors.
• That are violet, indigo, blue, green, yellow, orange, and red
• The bending depends upon the wavelength of the light.
• The prism act as the dispersion material. When white light passes through the prism it gets refracted from inner material and one comes out in the form of dispersed light with the seven colors.
• The red color deviates less as it has more wavelength.