Q.
A radioactive nucleus of mass number A , initially at rest, emits on α -particle with a speed v . What will be the recoil speed of the daughter nucleus?
Given that, the radioactive nucleus of mass number A , initially at rest, emits an α - particle with a speed v .
From conservation of linear momentum,
Initial moment before reaction = final momentum after reaction 0=4v−(A−4)v1 ⇒v1=(A−44v)
The recoil speed of the daughter nucleus will be =(A−44v)