Assume that a neutron breaks into a proton and an electron. The energy released during this process is (mass of neutron = `1.6725 xx 10^(-27)` kg, mass of proton = `1.6725 xx 10^(-27) kg`, mass of electron `= 9 xx 10^(-31) kg)`

Options

A. 5.4 MeV
B. 0.51 MeV
C. 7.10 MeV
D. 6.30 MeV

Answer

B

Explanation

Energy `=Deltamc^(2)`
`=(m_(p) xx m_(n)) (3 xx 10^(8))^(2)`
`=m_(e) xx 9 xx 10^(16)= 9 xx 10^(-31) xx 9 xx 10^(16)` J
`=(81 xx 10^(-15))/(1.6 xx 10^(-19)) eV = 50.625 xx 10^(4)` eV
`=0.50626 xx 10^(6)` eV = 0.51 MeV