Question

Sir,

I am Shaun job of class 10, I have a doubt in physics on the topic of optics,

This is the question Sir

If the Rayleigh scattering holds good, then the intensity of scattering is inversely proportional to the fourth power of the wavelength, then when sunlight enters the earth's atmosphere, the violet light should get scattered the most and blue light also gets scattered, but less than violet light, so my question is why doesnt the sky appear violet instead of blue??

Thank you Sir

Shaun

Answer 1

It is explained on the basis of the sensitivity of our eye's color receptors. Our eye is more sensitive to blue than violet or other UV radiations. Another point is that the emission intensity of solar spectra is not constant through out the spectra. the sensitivity of our eyes: Our eyes are more sensitive to blue than they are to violet. Combine the two effects and it means our eyes don't pick up nearly as much violet light as they do blue.Because violet is spatially (angularly) separated in a rainbow: the retina cones detecting violet and blue are spatially separated. For the sky colour the same detectors are at work for both blue and violet and since they are more sensitive in the blue part of the spectrum the sky is blue.