Answer:
4 Km/hr
Step-by-step explanation:
Data obtained from the question include the following:
Mass of ball (Mb) = 15 Kg
Velocity of ball (Vb) = 20 Km/hr
Mass skater (Ms) = 60 Kg
Velocity of skater (Vs) = 0 Km/hr
Velocity after collision (V) =..?
Thus, we can obtain the velocity after collision as follow:
MbVb + MsVs = V(Mb + Ms)
(15 x 20) + (60 x 0) = V (15 + 60)
300 + 0 = 75V
300 = 75V
Divide both side by 75
V = 300/75
V = 4 Km/hr.
Therefore, the velocity after the collision is 4 Km/hr.