Momentum of Photon with Energy of 2500000 Ergs: 8.3*10^-10 J*s/m

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The discussion focuses on calculating the momentum of a photon with an energy of 2,500,000 ergs, which converts to 0.25 joules. The momentum is derived using the formula p = E/c, resulting in a value of 8.3 x 10^-10 J*s/m. There is some confusion regarding the units, with participants debating whether to express the answer as J*s/m or Newton seconds. Ultimately, it is clarified that both expressions represent the same physical quantity. The conversation emphasizes the importance of unit clarity in physics calculations.
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Can someone please check over my solution and let me know if its right or wrong? Thank you.

question:calculate the momentum if the energy of photon is 25 x 10^5 erg?

solution:
2500000 Ergs = 0.25 Joules

p=E/c
(0.25 J)/(3*10^8 m/s)= 8.3*10^-10 J*s/m
 
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Hi melissajohn,

melissajohn said:
Can someone please check over my solution and let me know if its right or wrong? Thank you.

question:calculate the momentum if the energy of photon is 25 x 10^5 erg?

solution:
2500000 Ergs = 0.25 Joules

p=E/c
(0.25 J)/(3*10^8 m/s)= 8.3*10^-10 J*s/m

That looks right to me.
 


ok thanks!... I wasn't sure if the answer was

= 8.3*10^-10 J*s/m

or 8.3*10^-10 Newton seconds

because of the units...
 


Newton seconds would probably be a more exact answer, even though it appears to me that that's the same as a Joule * s/m.
 
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