In an `alpha` -decay, the kinetic energy of `alpha`-particles is `48 MeV` and `Q` value of the reaction is `50 MeV`. The mass number of the mother nucleus is (assume that daughter nucleus is in ground state)

Options

A. `96`
B. `100`
C. `104`
D. none of these

Answer

b

Explanation

Let, `._Z^4Xrarr._(A-2)^(A-4)Y+._(2)^(4)He`
`K_(alpha) =(m_(y))/((m_(y)) +(m_(alpha)))Q`
`=(A -4)/(A)Q`
or `48 =(A-4)/(A) xx 50 rArr A=100`.