if light does not have mass...

[Funmi Baruwa]

This question may be asking to understand too much, but I'm a little curious.

If we use De Broglie's equation to find the wavelength/show the wavelike properties of a particle, then how come the equation was derived from equations used for light?

I thought light does not have mass, so how can we use light as a reference for an equation that requires mass??

I hope my question makes sense lol

[Megan Sparrow 1A]

You are correct, light does not have mass. It does, however, have momentum. Since photons (particles of light) have no mass, they must obey E = pc and therefore get all of their energy from their momentum. This is why the DeBroglie equation works in this instance. Hope this helps!

[Funmi Baruwa]

thanks!! that clears it up :)