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PHYS - ENGR
Lv 4
How fast must an electron be moving if its energy is to be 9.67 times its rest energy?
An electron’s rest mass is 0.511 MeV/c2.
1 Answer
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- ?Lv 68 years agoFavorite Answer
You don't need to know the rest mass
energy = mc^2/(sqrt(1-(v/c)^2))
So:
energy/rest energy = 1/(sqrt(1-(v/c)^2))
9.67= 1/(sqrt(1-(v/c)^2))
Solve.
v/c = 0.9946
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