A neutron moving with a speed v strikes a hydrogen atom in ground state moving toward it with the same speed. Find the minimum speed of the neutron for which ineleastic (completely or partially) collision may take place .The mass of neutron = mass of hydrogen `= 1.67 xx 10^(-27)kg`

Answer

`4`

Explanation

In case of inelastic callision, the `H`-atom will be in excited state. The minimum energy will be when it is perfectly inelastic is, the two `(n)` and `(H)` both come to rest will move will same velocity i.e.,
`nV+vH " "rarrn+H`
from energy conservation
`2xx(1)/(2) mv^(2)=E " " v=sqrt((E)/(m))`,
`v=sqrt((10.2e)/(1.67xx10^(-27)))=3.13xx10^(4)m//s`
where `E` is the excitation energy