Multiple Choice
The positrons near the galactic center can be detected because they annihilate with electrons and emit gamma rays. Two gamma rays are produced in such a situation to conserve both energy and momentum. Suppose the positron and electron, each with energy mc2, convert all of this energy into two identical gamma-ray photons. What will be the wavelength of these photons? The mass of an electron is 9.1 * 10-31 kg.
A) 1.5 * 10-2 nm
B) 2.4 * 10-3 nm
C) 3.9* 10-4 nm
D) 7.9 *10-5 nm
Correct Answer:
Verified
Correct Answer:
Verified
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