EK Question: Wave and Particle Nature of Light

[jaybird12]

EK #172 (pg. 171 in 8th edition): "All of the following are indicative of the wave nature and not the particle nature of light EXCEPT: "
I said: C. dispersion
Correct answer: D. reflection

I thought that dispersion would be indicative of particle nature because its a way of making sure the rate of energy propagation stays the same (per this thread: http://forums.studentdoctor.net/threads/tbr-wave-frequency-v-speed.1091497/), so that higher energy photons don't get through to the other side so fast. But because of E = hf, I guess the energy of photons is also related to the frequency of the light. So wouldn't dispersion be indicative of both wave and particle nature?
And the answer in the book says that "Reflection is indicative of either wave or particle theory." How?

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[The Brown Knight]

sorry if my post on your other thread misled you in a practice question!

the question does seem a bit ambiguous, but here's what I would think:
1) reflection CAN be explained via particle theory if you just imaging the photons as little balls colliding with a smooth surface; the following article explains it way better and in fact makes the case for particle theory being more dominant in explaining reflection (since it also accounts for reflection from rough uneven surfaces) :
http://www.micro.magnet.fsu.edu/primer/java/particleorwave/reflection/index.html

2) an argument that I have for dispersion explained primarily from wave model is this: when the light moves into a glass prism, its frequency stays the same and only its velocity and WAVELENGTH change; a particle can have a frequency (photoelectric effect: e.g. photons exciting electrons on metal surface) but you can measure the wavelength only of a wave; the last paragraph of the following article also says that refraction, which is what chromatic dispersion is based on, can't be explained by particle theory very well (how would you explain particles changing direction after traversing a different medium?):
http://micro.magnet.fsu.edu/primer/java/particleorwave/refraction/

 

[jaybird12]

No, thank you, your way of thinking about chromatic dispersion made the most sense of anything I could find.
Okay, I think the reflection vs. refraction/dispersion thing makes sense. The wave vs. particle duality is inherently confusing, but it makes more sense now. Thank you!!