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Name: Adam M.
Status: educator
Age: 30s
Location: N/A
Country: N/A
Date: 5/15/2003

How do you explain single slit diffraction to a general Physics student?


Single slit diffraction works under the same principle as double slit. The slit has a width. Signal emanates forward from everywhere between the slit's sides. IMAGINE the slit as two halves. Consider an angle where light from the left edge of one half is perfectly out of phase with light from the left edge of the other half. At that same angle, light from every location in one half is put of phase with light from the corresponding location in the other half. All together, one half cancels the other: completely destructive interference, a dark spot. A single slit is like two "half-slits" that actually touch each other.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College

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