De Broglie's Equation

[Aayush Patel 3B]

Why can't De Broglie's Equation be used for light in order to find its frequency or wavelength?

[Maria Poblete 2C]

I believe that De Broglie's Equation can only be used for particles with a mass. I don't think light has a mass, so it wouldn't make sense to use the equation when mass is needed as a variable.

[gabbymaraziti]

De Broglie's equation is reserved for objects that mass, like electrons, cars, or baseballs. Since light is, by definition, mass-less, De Broglie's equation does not apply. The wavelength of light can be determined given the speed and frequency of the light wave, as wavelength = c/v.