Question

Rarefaction occurs only in a _______ wave.

A. transverse.
B. longitudinal.
C. forced.
D. sympathetic
User:
When a sound from a source is refracted away from the surface of the earth, it gives an indication that the
A. ground is cooling faster than the air.
B. air is cooler than the ground.
C. wind is blowing in the direction of the sound.
D. air has high humidity.

Answer 1

1.B Longitudial

2.B air is cooler than the ground

Step-by-step explanation:

Answer 2

Answers

1) B. longitudinal.

2) B. air is cooler than the ground.

Explanation

Q1

There are two categories of a wave. That is transverse and longitudinal waves. Transverse waves forms crests and troughs while longitudinal forms compressions and rarefaction as they travel. Rarefactions are regions where the wavelengths are longer than other regions.

Q2

As the ray of light moves from an optically less dense to a more dense region it bends towards the normal.

If the sound is bending away from the earth's surface, then the ground must be warmer than the air. As the sound travels it moves from optically dense medium to a less dense medium. For this reason it bends away from the normal. This can only happen when, B. air is cooler than the ground.