The rest energy of an electron is.

Options

A. 510 KeV
B. 931 Ke V
C. 510 Me V
D. 931 Me V

Answer

A

Explanation

Rest energy of an electron = `m_(e) c^(2)`
Here `m_(e) = 9.1 xx 10^(-31) kg ` and `C` = velocity of light
`therefore` Rest energy `= 9.1 xx 10^(-31) xx (3 xx 10^(8))^(2)` joule
`= (9.1 xx 10^(-31) xx ( 3 xx 10^(8))^(2))/(1.6 xx 10^(-19)) eV ~~ 510` Ke V