PRE-ASSESSMENT A student is sitting on the side of the highway to the danger zone. They
notice a Toyota Prius pass right in front of them and close their eyes in
disgust for 3 seconds. When they open their eyes, the car is 30m further
away. What is the car's velocity?
A 60 m/s
B 90 m/s
C 10 m/s
D 30 m/s
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RI

The Toyota's speed is 10 m/s. There's not enough information to state its velocity.

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.