mark asked in Science & MathematicsPhysics · 4 years ago

What does it mean?

Photons don t have rest mass but they do have energy and hence mass.I don t know , I picked up this statement from somewhere and I was like whatttt? So please answer this question?

2 Answers

  • 4 years ago
    Favourite answer

    No, photons do not have mass.

    The equation E = mc^2 relates energy and mass, in that energy and mass can be converted, one to the other. What it does NOT say is that a photon (which is energy) also has mass.

    But that equation is actually a short form. The full equation is

    E^2 = m^2*c^4 + p^2*c^2

    Where p is momentum. So while a photon has zero mass, it's energy has a momentum equivalent.

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  • D g
    Lv 7
    4 years ago

    Photons have 0 rest mass

    Rest mass is mass of object when at rest

    Since photons always move at light speed they cannot exist at 0 m per second

    If you look at relativity equations for mass the photon moving at c can have mass

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