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Hi

I am not too sure but I had my physics exam the other day.I think it went great although I am much confused on few problems now when I come to think of them.Question first asked for me to find kinetic energy of a photon. So using 1/2mv^2 I got that value later on it asked me to find out the momentum of a photon.Now the wavelength was given to be around 660nm I plugged that into p = h/lamda. Now I think thats one way to do it or by having my K.e = value manipulating it such that mv = 2v times my k.e value. Now which is right or wrong :S ? :( Sorry but I just cant recall the values other than lamda which I posted above.

The next part of the question was quite complicated. They had Power of laser given as 1x10^-3 W and using force = change in momentum I had to find force.

So I used E (energy) = hc/lamda to get my energy value.Then by manipulation I got the time from power = energy/time. That time got plugged into force equation.

I hope I making any sense at all.

All inputs are greatly appreciated.

Thank you.

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3. The attempt at a solution

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# Homework Help: Photon momentum

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