Interference - Finding distance between slits

1. Apr 1, 2009

mattbonner

1. The problem statement, all variables and given/known data
A laser is shone through a set of slits and onto a screen.
I have a Δy vs. L graph plotted, where Δy is the spacing between successive nodes, and L is the distance from the slits to the screen. I'm supposed to find the spacing between the center of the slits. The value of λ is given.

2. Relevant equations
Δy = λL/D
y is the spacing between successive nodes
L is the distance from the slits to the screen
D is the spacing between the center of the slits

3. The attempt at a solution
I have the slope, but I don't know where to go from there...
I'm thinking that the slope will be equal to λ/D? and if I know λ, then I can calculate D. Not sure if this is the right way to go though.

Last edited: Apr 1, 2009
2. Apr 1, 2009

Redbelly98

Staff Emeritus
Yes, that's right.