• Lvxferre [he/him]@mander.xyz
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    2 days ago

    You certainly know it, but sharing it for the ones who don’t:

    The full equation is = (pc)² + (m₀c²)² where E, p, c, m₀ are respectively: energy, momentum, the speed of light, inertial mass. The (pc)² part is kind of a big deal, because otherwise massless particles (like photons) would have no energy.

    If p = 0, then the equation simplifies into that famous E=mc².

    • Karyoplasma@discuss.tchncs.de
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      2 days ago

      What I think is funny is that if you assumed E=mc^2 for all particles, then that would mean that red light is lighter than blue light.

      • Lvxferre [he/him]@mander.xyz
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        2 days ago

        This, too: if E = hc/λ and E = mc², then we can combine both as hc/λ = mc². Rearranging this shit you get m = h/λc. Since h/c = 2.2*10⁻⁴²kg*m, you’d get:

        Photon colour wavelength (in nm) “Weight” (in 10⁻³⁶kg = 10⁻³qg)
        red 650 3.4
        yellow 600 3.7
        green 550 4.0
        blue 450 4.9

        …BLOODY ULTRAVIOLET IS MAKING ME FAT!