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

Answer:

3/5 v

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:

$VA_f=(\frac{m_A-m_B}{m_A+m_B})VA_i+(\frac{2m_B}{m_A+m_B})VB_i$

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:-

$VA_f=(\frac{4m-m}{4m+m})v$

$\\VA_f=\frac{3m}{5m}v$

$\\VA_f=\frac{3}{5}v$

Therefore the correct answer is $\frac{3}{5}v$