Question

A proton of mass m is at rest when it is suddenly struck head-on by an alpha particle (which consistsof 2 protons and 2 neutrons) moving at speed v. If the collision is perfectly elastic, what speed will the alpha particle have after the collision

Answer 1

3/5 v

Step-by-step explanation:

The computation of speed will the alpha particle have after the collision is shown below:-

In a perfectly elastic the kinetic energy and collision the momentum are considered.

The velocity of the particles defines the below equation:

`VA_f=((m_A-m_B)/(m_A+m_B))VA_i+((2m_B)/(m_A+m_B))VB_i`

As we know that

`VA_i=v`

`\\VB_i=0`

Here, we consider A is the alpha particle and B is the proton and now by the above values we can solve the equation which is below:-

`VA_f=((4m-m)/(4m+m))v`

`\\VA_f=(3m)/(5m)v`

`\\VA_f=(3)/(5)v`

Therefore the correct answer is
`(3)/(5)v`