a motorcycle traveling on the highway at a velocity of 120 kilometre-per-hour passes a car traveling at a velocity of 90 kilometre-per-hour from the point of view of a passenger on the car what is the velocity of a motorcycle

The relative velocity of the motorcycle to a passenger in the car is 30 km/h

Explanation:

The question relates to the principle of relative velocity and reference frames

The given parameters are;

The velocity of the motorcycle, v₁ = 120 km/h

The velocity of the car, v₂ = 90 km/h

The relative velocity of an object X with regards to another object Y is the velocity the object X will seem to be moving with to an observer in the rest frame of object Y written as = -

Therefore, the relative velocity of the motorcycle to the car is = v₁ -  v₂, which give;

 = 120 km/h - 90 km/h = 30 km/h

The relative velocity of the motorcycle to a passenger in the car = 30 km/h.

are you like autistic or something?

xd

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.