Answer:
[tex]\displaystyle v_2'=7.5\ m/s[/tex]
Explanation:
Conservation Of Linear Momentum
The total momentum of both balls won't change regardless of their interaction while no external forces are acting on the system. We'll use the following variables m1,m2,v1,v2,v1',v2' for the mass of the white ball, the mass of the red ball, their velocities before the collision, and their velocities after the collision, respectively .
The provided data is as follows:
[tex]\displaystyle m_1=143\ gr=0.143\ kg[/tex]
[tex]\displaystyle v_1=7.9\ m/s[/tex]
[tex]\displaystyle m_2=150\ gr=0.15\ kg[/tex]
[tex]\displaystyle v_2=0[/tex]
[tex]\displaystyle v_1'=0[/tex]
To preserve the total linear momentum, the following equation must stand
[tex]\displaystyle m_1\ v_1+m_2\ v_2=m_1\ v_1'+m_2\ v_2'[/tex]
Solving for [tex]v_2'[/tex]
[tex]\displaystyle v_2'=\frac{m_1\ v_1+m_2\ v_2-m_1\ v_1'}{m_2}[/tex]
[tex]\displaystyle v_2'=\frac{0.143(7.9)+0-0}{0.15}[/tex]
The final speed of the red ball is
[tex]\boxed{\displaystyle v_2'=7.5\ m/s}[/tex]
