Answer: 3 m/s
Explanation:
We can solve the problem by using the law of conservation of momentum: during the collision between the two balls, the total momentum of the system before the collision and after the collision must be conserved:
[tex]p_i = p_f[/tex]
The total momentum before the collision is given only by the cue ball, since the solid ball is initially at rest, therefore
[tex]p_i = m_c u_c = (0.5 kg)(3 m/s)=1.5 kg m/s[/tex]
So, the final total momentum will also be
[tex]p_f = 1.5 kg m/s[/tex]
And the total momentum after the collision is given only by the solid ball, since the cue ball is now at rest, therefore:
[tex]p_f = m_s v_s[/tex]
from which we find the velocity of the solid ball
[tex]v_s = \frac{p_f}{m_s}=\frac{1.5 kg m/s}{0.5 kg}=3 m/s[/tex]
