I'm just wondering about this when you are making calculations of photon mass. For instance, determining the mass of a photon travelling at the speed of light and having a frequency of 100 Hz. Which equation do you use, KE = 0.5mv^2 or do you use E=mc^2 (both in conjunction with the E=hf formula).(adsbygoogle = window.adsbygoogle || []).push({});

Thanks!

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# Determining the mass of a photon travelling at the speed of light

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