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If all photons have the same speed (the speed of light) and the same mass (zero), why does an individual gamma-ray photon have more energy than a radio-wave photon?

Stephen Kahofer, Clifton, New Jersey
RELATED TOPICS: SPACE PHYSICS
Photons
The answer to this question stems from Albert Einstein’s ideas. The equation E=mc2 states that mass (m) and energy (E) are manifestations of the same thing; mass can change into energy, and energy can change into mass. The speed of light (c) is the “conversion factor” between the two quantities.

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