National Science Day: 'Raman Effect' that won India's 1st Physics Nobel
India observes February 28 as ‘National Science Day’ to mark the discovery of ‘Raman Effect’ by Sir CV Raman on February 28, 1928, the discovery for which he was awarded the Nobel Prize in Physics in 1930. But what exactly is Raman Effect? Let’s try to understand Rayleigh scattering Before diving into the Raman Effect, it is important to first understand its background. It all started with the ‘Rayleigh scattering’, a theory proposed by British physicist Lord Rayleigh, in which he answered the most basic question: Why is the sky blue? His theory stated that when sunlight interacts with air particles, it gets scattered. Because light is made up of different colours, the degree of scattering depends on the wavelength of the colour. Since violet and blue colours have low wavelengths, they get scattered the most. But because human eyes are more sensitive to the blue colour, the sky appears blue. Rayleigh then argued that the blue colour of the ocean is the mere reflection of the blue c...