Blue colour of sea water is due to

Why are clouds seen to be of white colour?

Write a note on rainbow.

What will be the colour of the sky as seen from the Earth if there were no atmosphere?

If the scattering intensity of a liquid is $8 \text{ units}$ at a wavelength of $500 \text{ nm}$, then the scattering intensity at a wavelength of $400 \text{ nm}$ will be approximately: (in $\text{ units}$)

The reason for seeing the Sun a little before the sunrise is: