How can photons have momentum?

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Answer 1 · 2016-05-28T14:23:01

Photons have energy which means that they also have momentum.

Photons have zero mass and travel at the speed of light. The relationship between the energy, momentum and the speed of light is given by:

$E = p c$ $E=pc$

Where $E = \frac{h c}{λ}$ $E=(hc)/lambda$

$(hcancel(c))/lambda=pcancel(c)$

$p=h/lambda$

$h$ is the Planck constant, $c$ is the speed of light and $lambda$ is the wavelength of the light and $p$ is the momentum.

So, photons have momentum because they have energy.