Answer:
0.49 m/s
Explanation:
The law of conservation of linear momentum states that the sum of momentum in a system before and after collision are same. Momentum is a product of mass and velocity of an object hence in this case
[tex]m_cu_c+m_8u_8=m_cv_u+m_8v_8[/tex]
Where m represent mass, u and v represent the initial and final velocities respectively, subscripts c and 8 represent cue ball and number 8 ball respectively.
Since number 8 ball is initially at rest, its initial velocity is zero. Replacing mass of cue ball with 170 g while mass of number 8 ball with 160g, then taking final velocity of cue ball as 0.2 m/s and final velocity of 8 ball as 0.3 m/s then we get
[tex]170u_c+160*0=170*0.2+170*0.3\\u_c\approx 0.49 m/s[/tex]
