Question

What did C. V. Raman discover, the phenomenon for which he was awarded the Nobel Prize in Physics?

Hint:

Think about what happens to the wavelength of light after scattering, and why this effect won a Nobel Prize.

Answer 1

Step 1: In 1928, C. V. Raman studied what happens when a beam of monochromatic light, meaning light of a single wavelength, passes through a transparent substance such as a liquid.

Step 2: He found that most of the scattered light kept the same wavelength as the incoming light, but a small fraction of the scattered light came out with a different wavelength, either slightly longer or slightly shorter.

Step 3: This change in wavelength happens because the light photons exchange energy with the vibrating or rotating molecules of the substance, gaining or losing a small fixed amount of energy in the process. Because energy is exchanged, this is called inelastic scattering.

Step 4: This effect was named the Raman effect in his honour, and it earned him the Nobel Prize in Physics in 1930, making him the first Asian to win a Nobel Prize in science.

Answer: C. V. Raman discovered the Raman effect, the inelastic scattering of light by molecules, in which scattered light shows a change in wavelength from the incident light.