• mvirts@lemmy.worldEnglish
    0·
    17 days ago

    E=mc^2 so m is joule seconds^2 / meter ^ 2

    F=ma so m is Newton seconds^2 / meter

    A joule is 1 Newton / meter so they agree

      • absGeekNZ@lemmy.nzEnglish
        0·
        17 days ago

        A J = Ns not N/s

        One Joule of energy is one Newton of force applied for 1 second.

        • zkfcfbzr@lemmy.worldEnglish
          0·
          17 days ago

          Muphry’s law at work - for both of us, actually. I looked it up (since with Ns the units no longer worked out between E = mc² and F = ma), and a joule is actually a Nm, a Newton-meter. And with that the units do work out correctly on both equations.

          • absGeekNZ@lemmy.nzEnglish
            0·
            17 days ago

            That is really unintuative, torque is Nm…how can energy also be Nm.

            But then I look at it and J = Ws = N(m/s)s = Nm