Does light weigh anything? © Getty Images

Does light weigh anything?

As light as a feather... or even more so? Just how massive is light?

Asked by: Anonymous


Light is a form of electromagnetic (EM) radiation, and theory shows that the mass of photons f light is related to the range of this radiation. If, as most scientists believe, EM radiation has an infinite range, then photons must be massless. That said, light possesses energy and so, by Einstein’s famous equation E = mc2, it can still behave as if it has mass-like properties.


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