how can a photon have mass?

Question

anonymous · Answer

It has mass. It's rest mass is zero. When in motion, it has a momentum. Hence mass.

unklerhaukus · Answer

A photon has momentum, but it does not have mass.

aaronq · Answer

attachment

anonymous · Answer

According to the special theory of relativity total energy and mass of a system is conserved.
As we know that photon is a form of energy, therfore a photon associated system must have some associated mass. This arises the concept that photon must have some mass.
However being a form of energy its rest mass is 0. But when it is moving at a very high speed, going by quantum mechanics, it has some associated mass which may b given the following equation attached.
Also when photon moves with speed of light its mass bcomes indeterminate|dw:1373221828534:dw|

anonymous · Answer

rest mass of photon is 0 but it does have moving mass which could be calculated from E=mc^2 ... first calculate energy from E=hf ... h is plancks constant nd f is frequency of photon