Why do sound waves move faster through the ground than through the air?

particles of matter are packed more loosely in the ground than in the air.

particles of matter are packed more tightly in the ground than in the air.

air doesn’t contain any particles of matter to transmit sound waves.

the elevation of the ground is lower than the elevation of the air space.

Particles of matter are packed more tightly in the ground than in the air.

Explanation:

As we know that velocity of sound in a given medium is given by formula

here we know that

E = elasticity of the medium

= density of the medium

now we know that if we increase the density of medium then particles of matter are packed more which will decrease the speed of wave.

while is particles are tightly packed then it will increase the elasticity of the medium

So here if all particles are tightly bounded with each other then sound waves will move faster through the medium

a. are

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.