Question

Draw a ray diagram showing the dispersion through a prism when a narrow beam of white light is incident on one of its refracting surfaces. Also indicate the order of the colors of the spectrum obtained.

Answer 1

Explanation:

1. Dispersion is the phenomenon of splitting white light into its constituent colors
2. Dispersion happens due to the difference in the speed of electromagnetic waves for different frequencies.
3. The bending of the light is inversely proportional to the wavelength of light, thus, the red light bends less as compared to the violet.

Given below are the order of colors obtained during the dispersion of white light through a prism.

The order of color obtained is

1. Violet – 4000 Å to 4240 Å
2. Indigo – 4240 Å to 4500 Å
3. Blue – 4500 Å to 4912 Å
4. Green – 4912 Å to 5750 Å
5. Yellow – 5750 Å to 5850 Å
6. Orange – 5850 Å to 6470 Å
7. Red – 6470 Å to 7000 Å

Given below is the diagram that shows the dispersion of white light through a prism-