Mistake Master
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Mistake Master · AP Physics 2 · Unit 15 · Step-Through Animation

Three Participants, Not Two

You'll learnthat the photon survives the collision rather than being swallowed, that the shift is added onto the incoming wavelength rather than replacing it, and that the size of the shift depends on the scattering angle and on nothing else.

Fire an X-ray at a loosely held electron and it bounces away, longer in wavelength and lower in energy, while the electron recoils with the difference: light behaving exactly like a billiard ball. Eleven short steps; press Next for each one.

11 STEPS · 6 QUICK CHECKS · THE PHOTON SURVIVES · THE SHIFT IS ADDED ON · v2

the photon survives · the shift is added on · only the angle matters
Before you start
What you're looking at
A collision seen from the side: an X-ray photon arrives from the left and meets an electron at rest.
The question
Does the photon survive, what wavelength does it leave with, and what sets the size of the shift?
Step 1 / 11