Photon energy vs. wavelength
Compared with a red photon (700 nm), a blue photon (450 nm) has:
Answer C: explanation for every choice
A
Higher frequency always means higher energy.
B
All photons travel at c in a vacuum, and energy depends on frequency.
C
Correct. E = hf = hc/λ, so a shorter wavelength means higher frequency and energy.
D
Shorter wavelength means higher, not lower, frequency.
TakeawayE = hf = hc/λ. Shorter wavelength, more energy.
Equation usedPhoton energy
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