Momentum of a Photon - Is My Understanding Correct?

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A photon’s momentum is defined as p = E/c, where E is its energy, and it can be expressed in terms of frequency as p = hν/c. When a photon collides with another particle, the change in momentum can be calculated using the formula Δp = (h/c)(f2 - f1), where f1 and f2 are the initial and final frequencies of the photon. This concept is illustrated by the Compton effect, which demonstrates how energy and momentum change during photon-particle interactions. Understanding these relationships clarifies the nature of photon momentum and its implications in physics.
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This thing has troubled me for a long time.. but i think this is eventually starting to get clear to me.

When we say a photon has a momentum 'p', the momentum isn't it's mass times the velocity.. but it can be interpreted as: If the photon [having frequency f_1] collides with any other particle, and an elastic collision takes place.. and it's frequency now is f_2, then the momentum imparted to the particle is: \Delta p = \frac{h}{c}(f_2 - f_1)[/itex]<br /> <br /> am i right?
 
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For a photon, momentum, p = E/c = h\nu/c, and a change would be given by

\Delta p = \frac{h}{c}{(f_2 - f_1)}, where h/c is a constant. I used nu for frequency f.
 
Astronuc said:
For a photon, momentum, p = E/c = h\nu/c, and a change would be given by

\Delta p = \frac{h}{c}{(f_2 - f_1)}, where h/c is a constant. I used nu for frequency f.

well.. i actually.. said the same thing. I don't get what you were trying to explain. Can u please explain? thanks.
 
rohanprabhu said:
well.. i actually.. said the same thing. I don't get what you were trying to explain. Can u please explain? thanks.
I was explaining that a photon of energy E and a momentum of p = E/c. When a photon scatters (interacts with a particle), there will a change in energy and momentum, and the change in p = (Ei - Ef)/c. This is demonstrated in the Compton effect.
 

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