# Constructive or destructive interference after a set number of waves?

1. Sep 11, 2014

### kontorstol

1. The problem statement, all variables and given/known data
Two sources, S1 and S2, send our circular waves that are in phase and of the same frequency. They have the same wavelength (0,5m) and the same amplitude. Will there be a maxima og a minima at the given points:

a) S1P = 5.00 m og S2P = 6.50 m?

b) S1P = 5.00 m og S2P = 4.75 m?

2. Relevant equations
No equations that I can find.

3. The attempt at a solution
I have tried to draw the waves from two points, but it ended up as a mess. I have tried to find some equations for finding this, but I have not found any.

If someone got the time, I would prefer a explanation, and not just an answer. Thank you. :)

2. Sep 12, 2014

### andrevdh

No info on how far apart the two sources are?

3. Sep 12, 2014

### nrqed

I don't know what "o g" means :-)

I am assuming they are given the distances to the two sources. Then just look at |S1P-S2P| which is the path difference and see how many wavelengths fit in those intervals. This leads to the answer.