# Warm-Up Exercise 34

## Due 12:15 pm, Wed 14 Nov 2012

Physics 123, Fall 2012

As shown below, the diffraction pattern of a single slit has a broad maximum in the middle, then narrower maxima to the sides. How does the intensity of the broad middle peak compare to the intensity of the closest side peaks?
☑ Broad peak is a lot more intense
☐ Broad peak is a little more intense
☐ Same intensity
☐ Side peaks are a lot more intense
☐ Side peaks are a little more intense

(You can see this from the expanded image now shown just below.)

This is the diffraction pattern for a single wide slit. What will happen to the pattern if the slit is made narrower?

If the slit is made narrower ("a" decreases), then the spacing between minima and maxima will increase. That is, the pattern will spread out.

This is the diffraction pattern for two wide slits. (a) What will happen here if the distance between slits is made narrower? (b) What is the distance is held constant but the width of each slit is made narrower.

(a) If the distance between slits is made narrower, the "fringes" (high frequency oscillation) will spread out, but the "diffraction minima" (low frequency oscillation) will stay in the same places. (b) If the width of each slit is made narrower, the diffraction minima will spread out but the interference fringes will stay in the same places.