The rest mass of an electron as well as that of positron is 0.51 MeV. – McqOptions

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1.	The rest mass of an electron as well as that of positron is 0.51 MeV. When an electron and positron are annihilate, they produce gamma-rays of wavelength(s) [UPSEAT 2002]
A.	0.012 Å
B.	0.024 Å
C.	0.012 Å to ¥
D.	0.024 Å to ¥
Answer» B. 0.024 Å

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