30 points answer asap
a billiard ball with momentum of 20 kg * m/s strikes a second ball at rest and comes to a complete stop what is the change in momentum of the second ball

Explanation:

Momentum of the system is a constant when there aren't external forces..

So,When first Balls velocity is went down to zero... its momentum is also zero and beacause momentum should be a constant...now second ball must have a momentum of 20 kg * m/s

if the thermos has a vacuum innner, then heat through conv currents and conduction are reduced = vacuum flask

scattering of light by tiny particles in air to produce the colors we see on sky, is dependent on the following factors:

(i) wavelength of light

(ii) size of the scattering particle  

(iii) distance traveled by light through the atmosphere.

according to rayleigh's law of scattering, the amount of scattering is inversely proportional to the fourth power of its wavelength. shorter the wavelength, greater is its scattering. hence violet/blue light is scattered more than red.

sun's light is a composite light ( visible light) with wavelengths in the range 400 nm (violet) to 700 nm (red). as sunlight passes through our atmosphere, the molecules of air scatter light according to their wavelengths. during sunrise and sunset, the sun's position is below the horizon. hence light from the sun travels a greater distance in the atmosphere when compared to its position a noon.

as sunlight enters the earth's atmosphere, blue light is scattered away and at the end of its journey in the sky, only red and orange wavelengths remain in the beam.

hence at sunrise and sunset, the sky appears reddish orange.