DL=|L2-L1|=xx l
f= xx p
Due to both wave 1 and wave 2 (the resultant)
Due to wave 2 only
Due to wave 1 only
Displacements of air particles at P
interference
Wave 2
L2
S2
S1
L1
Wave 1
| |
The interference of the two waves
at P is
fully constructive |
The interference of the two waves
at P is
fully destructive |
|
Path difference DL
between the two waves at P |
0, 1l, 2l,
... |
l/2,
3l/2,
5l/2, ... |
|
Phase difference f
between the two waves at P |
0, 2p, 4p,
... |
1p, 3p,
5p, ... |
| |
The two waves are in phase at P |
The two waves
are out of phase at P |
The sound point sources S1 and S2 are in phase.
Interference and phase difference
2-4 Interference
P
Click on S1, S2, or P and drag them
to change the two waves path length difference DL = |L2-L1|.