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Q & A: does light have mass?

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Most recent answer: 07/07/2016
Q:
My question is on photons and the speed of light.As far as I am aware photons have momentum, and are affected by gravity, so my reasoning is they must have, in some sense, mass, though I am yet to find a straight answer on whether this is the case or not...If photons are not strictly massless particles, then could a hypothetical particle with less mass than a photon travel faster than the speed of light?If photons are massless particles, how can the "speed" of light be defined, and how does light travel/how is it propelled?
- Reuben Baverstock (age 21)
Beckley, East Sussex, England
A:

This should answer your question:

https://van.physics.illinois.edu/qa/listing.php?id=16351.

Mike W.


(published on 07/07/2016)

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