3 ms·

> Light can transfer momentum Momentum is mass x velocity; what’s the mass of a photon?

• ace2358 3y ago
  E = ħf = mc^2. For photon, p = hλ
• FourHand451 3y ago
  You can't use classical physics to calculate the momentum of a photon. https://en.wikipedia.org/wiki/Photon#Relativistic_energy_and_momentum https://en.wikipedia.org/wiki/Photon#Relativistic_energy_and...
  • floxy 3y ago
    Classical electromagnetic waves from Maxwell's equations (i.e. non-quantized) also carry momentum, right? https://www.youtube.com/watch?v=bvzr2HbbPC8 https://www.youtube.com/watch?v=bvzr2HbbPC8 (Maxwell's equations are consistent with relativity) ...or another way of looking at it (that I presume Boltzmann would agree with). If your had a single black body mass at some temperature greater than absolute zero in an otherwise empty universe, it would radiate away heat and thus cool off. The cooler body means the individual atoms in the mass have less energy and less momentum. If momentum is conserved, then that momentum must have been carried away from the mass in the mass-less radiation. Another neat thing is that light can also have angular momentum.
• sdfghswe 3y ago
  > > Light can transfer momentum > Momentum is mass x velocity; what’s the mass of a photon? Photons have zero mass. What's your point?
• deleted 3y ago
  [deleted]