Waves and sound

  • Thread starter Yatin
  • Start date
  • #1
20
1
Hi guys. Was studying waves and got a bit confused. Pl help me out.

Coherent sources are those which produce waves of same frequency, wavelength and velocity. Amplitude need not necessarily be same. Am I right?

There's another doubt in my mind...

If two waves produce beats then which of the following quantities are necessarily same for both of them
Angular wave number( and thus wavelength)
Angular frequency ( and thus frequecy)
Velocity of wave
Amplitude

Please answer only if 100% sure.
 

Answers and Replies

  • #2
3,757
424
For coherence, they must have the same phase relationship. At least during the coherence time.
The wavelength depends on frequency and phase velocity so it is not an independent quantity.

For beats you need to have slightly different frequencies. Amplitudes can be different but then the minims won't be zero.
 
  • #3
20
1
For coherence, they must have the same phase relationship.
What do you mean by same phase relationship?
Is my notion about coherent waves correct?
 
  • #4
20
1
Angular wave number( and thus wavelength)
Angular frequency ( and thus frequecy)
Velocity of wave
Amplitude
So none of these have to be necessarily same for 2 waves to produce beats?
 
  • #5
sophiecentaur
Science Advisor
Gold Member
25,204
4,830
So none of these have to be necessarily same for 2 waves to produce beats?
You will not get beats of the two waves are of the same frequency and youdo not move the measuring position or sources; the phase relationship of the two waves stay the same at a given point so the resultant is the same amplitude.
 

Related Threads on Waves and sound

  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
8
Views
2K
  • Last Post
Replies
3
Views
761
Replies
1
Views
874
  • Last Post
Replies
7
Views
3K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
3
Views
3K
  • Last Post
Replies
8
Views
2K
  • Last Post
Replies
20
Views
14K
Top