Calculate the change in momentum of a 0.140 kg baseball that starts at rest and is struck by a bat with a contact time of 0.32 seconds for 100 N.

32kgm/s

Explanation:

Given that,

impulse I = ?

Mass of baseball M = 0.140 kg

force F = 100 N

Time = 0.32 seconds

Recall that impulse of an object is the product of force and the time during which it acts, and impulse is also equal to change in momentum.

i.e Impulse = Force x Time

Also, Change in momentum = Force x Time

So, I = Ft = m(Vf - Vi)

hence, Change in momentum = Ft

Momentum = 100N x 0.32 seconds

Momentum = 32kgm/s

Thus, the change in momentum of the baseball is 32kgm/s

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.