If `M(A,Z)`, `M_(p)and M_(n)` denote the masses of the nucleus `._(Z)X^(A)`, proton and neutron respectively in units of U (where`1U=931MeV//c^(2)`) and B.E. represents its B.E. in MeV, then

Options

A. `M (A,Z) = ZM_(p) + (A -Z) M _(n) - BE`
B. `M (A, Z) = ZM_(p) + (A-Z) M _(n) - BE //C ^(2)`
C. `M (A,Z) = ZM_(p) + (A-Z) M _(n) + Be //C ^(2)`
D. `M (A,Z) = ZM_(p) + (A-Z) M _(n)+ BE`

Answer

C

Explanation

`ZM_(p)+ (A-Z) M _(n) - M (A,Z)` = mass defect `=(BE)/(c ^(2))`
`implies M (A,Z) = ZM_(p) + (A-Z) M _(n) - (BE)/(c ^(2))`