3 ms·

If photon travels at speed of light, then it has no mass ? But if it has no mass, it shouldn't bring any energy, though.

• 781 8y ago
  https://www.quora.com/How-can-photons-have-no-mass-and-yet-still-have-energy-given-that-E-mc-2 https://www.quora.com/How-can-photons-have-no-mass-and-yet-s...
• gus_massa 8y ago
  The protons in this device travel almost at the speed of light.