1. Interference patterns for the double slit experiment are shown, all with the same x scale (for the position on the wall), and all with the slits the same distance from the the wall. For which pattern are the two slits closest together?

2. C has the broadest pattern, and hence the closest slits
C has the broadest pattern, and hence the closest slits. If the slits in C are 10 microns apart, what is the slit separation for A? (You may use the small angle approximation.) A] 20 microns B] 30 microns C] 40 microns D] 900 microns E] cannot determine

3. Pattern A is three-fold narrower than C, so the slits are three-fold farther apart. 30 microns. What is the slit width for A compared with C? A] both are the same B] A’s slits are 3X larger than C’s C] A’s slits are 3X smaller than C’s.

4. All slits are the same width. The intensity maxima are 4 W/cm2
All slits are the same width. The intensity maxima are 4 W/cm2. What would be the intensity from ONE SLIT? (in W/cm2) A] 0 B] 1 C] sqrt(2) D] 2 E] 4

5. For 3 evenly spaced identical slits, what phasor diagram corresponds to a minimum in intensity?

6. What is the path difference at which this minimum occurs?
B] 
C] 
D] 
E] 

7. A B C D
Four identical slits make the interference pattern shown. Point 1 is at theta=0. What phasor diagram could correspond to point 2?

8. A B C D
Four identical slits make the interference pattern shown. Point 1 is at theta=0. What phasor diagram could correspond to point 3?