Calculate KE, E, p and f for proton.

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The discussion focuses on calculating the kinetic energy, total energy, momentum, velocity, and frequency for photons, electrons, and protons. The provided calculations yield specific values for each particle, with the proton's kinetic energy calculated as 0.0002 MeV and total energy as 938.0002 MeV. Concerns are raised about the rounding of the results, particularly the inconsistency in significant figures between the momentum and energy values. The need for verification of the proton's results is emphasized, as the calculations may not align with expected precision standards. Overall, the thread highlights the importance of consistent rounding in physics calculations.
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Homework Statement


photon(0 MeV), electron(0.511MeV), photon(938 MeV) have wavelength of 2.0*10^-15 m, 2.0pm. Calculate their kinetic energy, total energy, momentum, all in MeV, and velocity and frequency.

Homework Equations


E = K + mc^2
E^2 = (pc)^2 + (mc^2)^2
E=hf
λ=h/p

The Attempt at a Solution


for photon:
K 0.621 MeV
E 0.621 MeV
p 0.621 MeV/c
v 3*10^8 m/s
f 1.5*10^20 Hz

for electron:
K 0.292 MeV
E 0.803 MeV
p 0.62 MeV/c
v 0.77 c
f 1.94*10^22 Hz

for proton:
K 0.0002 MeV
E 938.0002 MeV
p 0.62 MeV/c
v 6.6*10^-4 c = 1.98*10^5 m/s
f 2.2*10^23 Hz

I am a little bit not sure about my results regarding proton's. Any help verifying my answers will be appreciated because I don't have answer for this problem.
 
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You're right, but your rounding is a little weird. You have only two digits for p, but then you have 7 digits for E. With any reasonable rounding, you would have 2/3 digits for E and just get 0 for K.
 
thank you.
 
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