What gives photons the energy to move at the speed they do

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Photons travel at the speed of light due to their massless nature, which allows them to maintain this speed regardless of their energy. They are considered pure kinetic energy and are created with this speed from the moment of their formation. The energy of a photon originates from various processes, such as an electron transitioning to a lower energy state in an atom, which results in photon emission. Additionally, excited atomic nuclei can release energy as gamma rays, while x-rays are produced when moving electrons collide with metal and lose kinetic energy. Understanding these mechanisms clarifies the source of energy that enables photons to move at their characteristic speed.
MaoIragorri
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I have a question...
what gives photons the energy to move at the speed they do?
 
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Photons always travel at the speed of light, regardless of their energy, because they are massless.
 


A photon is pure kinetic energy. It alway travels at the speed of light, from the moment it is created. It's more accurate to say a photon has no rest mass than to say that it's massless.
 


In wording that "what gives photons the energy", I wonder if the intent was to ask where the energy came from. There is always a source of the energy. If an electron in an atom drops to a lower energy state, for example, making a transition from the n=2 quantum number to the n=1 quantum number, it emits one photon. A nucleus that is in an excited state sometimes falls to a lower energy state, and gives off a gamma ray. An x-ray is given off when a moving electron hits a metal and loses its kinetic energy.
 

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