4 ms·
E=mc^2 doesn't mean that a photon has mass. Photons do produce gravitational effects due to their energy, but not in the same way as a particle with mass m. See
by red75prime 2y ago
E=mc^2 doesn't mean that a photon has mass. Photons do produce gravitational effects due to their energy, but not in the same way as a particle with mass m. See, for example, https://physics.stackexchange.com/a/6222 https://physics.stackexchange.com/a/6222
- CamperBob2 2y agoA photon has no rest mass but it most certainly has mass-energy equivalence.