Multiple Choice
Particles: Suppose you were to try to create a proton-antiproton pair by annihilation of two very high-energy gamma rays of the same wavelength heading toward each other. The proton and the anti-proton have the same masses, but opposite charges. What would be the minimum energy needed for each photon? (e = 1.60 × 10-19 C, mproton = 1.67 × 10-27 kg, c = 3.00 × 108 m/s)
A) 1.022 MeV
B) 12.2 MeV
C) 1880 MeV
D) 939 MeV
E) 223 MeV
Correct Answer:

Verified
Correct Answer:
Verified
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