Crest and trough
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the frequency
Yes. An electromagnetic wave follows a sine-wave pattern.
Coherent
which kind of sound is produced by sound waves with peaks that are very close together?
a peak of ond wave instantaneously merges with the trough, or bottom part of another wave and in that moment there is neither a peak or a trough so there is no wave; this is called destructive interference. the opposite can also happen when two peaks and troughs merge and create amplified waves; this is called constructive interference. destructively
As all EM waves do a constant speed ('c'). If the frequency increases (i.e. the waves are more frequent) the distance between the wave peaks (wavelength) must reduce. For visible light waves, this produces a 'blue shift.'
Peaks and valleys to not create water waves, they are characteristic elements of water waves.
Sound Waves
Yes. An electromagnetic wave follows a sine-wave pattern.
All of them. Electromagnetic, sound, even a water wave until it hits shore.
When waves of the same frequency are in phase they reinforce each other when their peaks and valleys occur at the same point. They add up.
CHiPs - 1977 Peaks and Valleys 2-1 was released on: USA: 16 September 1978
Coherent
It depends which country or region you are talking about.
The Smokies are named for the blue mist that always seems to hover around the peaks and valleys. The Cherokee called them shaconage, (shah-con-ah-jey) or "place of the blue smoke". The Smokies are named for the blue mist that always seems to hover around the peaks and valleys. The Cherokee called them shaconage, (shah-con-ah-jey) or "place of the blue smoke".
which kind of sound is produced by sound waves with peaks that are very close together?
If you have two waves, or two things in oscillation or two things in vibration; if the peaks (maximum amplitude) and valleys (maximum amplitude the other way) occur at the same time then they are in phase. If one wave peaks at the same time the other one is in a valley they are said to be 180 degrees out of phase.
All land in the universe.