Wave Definitions - Crest and Trough

[Peter G.]

Hi,

I have a test on the definitions of some terms. I was wondering whether the crest is the highest point in a wave or any point above the undisturbed position. And, also, whether the trough is the lowest point or any point under the undisturbed position.

Thanks,
Peter G.

 

[kuruman]

Yes, the crest is the highest point and the trough is the lowest point. The amplitude is half the distance between crest and trough.

 

[Peter G.]

Thanks for the quick response! Would you mind checking some of my other definitions?

Rarefaction: an area of decrease in density and pressure
Compression: an area of increase in density and pressure

Wave speed: The speed at which a wave travels - the product of wavelength and frequency

Wave intensity: A measure of energy flux averaged over a period of time - energy per unit area per unit time

Thanks once again,
Peter G.

 

[kuruman]

Looks good.

 

[rwisz]

Hello Peter G.,

Thank you for reaching out with your question about wave definitions. I can provide you with accurate and precise definitions for both crest and trough in relation to waves.

Firstly, the crest of a wave is indeed the highest point of the wave, or the point where the wave reaches its maximum height. This can also be referred to as the peak of the wave. In a transverse wave, such as an ocean wave, the crest is the point where the wave is at its highest point above the undisturbed position, or the level of the water before the wave passed through.

Secondly, the trough of a wave is the opposite of the crest. It is the lowest point of the wave, or the point where the wave reaches its minimum height. This can also be referred to as the bottom of the wave. In a transverse wave, the trough is the point where the wave is at its lowest point below the undisturbed position.

It is important to note that the undisturbed position, also known as the equilibrium position, is the position of the medium (such as water or air) before the wave passes through. Any point above or below this position can be considered a crest or trough, respectively.

I hope this helps clarify the definitions of crest and trough for you. Good luck on your test!

Best,