Question

Find the momentum of a photon with a frequency of 2.1 x 10¹⁸ Hz.

Group of answer choices

Photons don't have momentum

2.1e18 kg m/s

7.0e10 kg m/s

4.7e-19 kg m/s

4.6e-24 kg m/s

Answer 1

Ans: 4.6e-24 kg m/s.

Explanation:

we know if be the total energy of the particle and be the momentum then,

where is the rest mass of the particle and is the speed of light.

Now for proton , rest mass , = 0

Again we know if be the frequency then,

, where =plank constant.

given ,

Or , p=4.6e-24 kg m/s.

So momentum of photon is 4.6e-24 kg m/s.