Question

a 20kg ball moving with a velocity of 6m/s collides with a 30 kg ball initially at rest. If both of them coalesce then the final velocity of the combined mass is

Answer 1

Dear Student,


$$\begin{gathered} m=20kg,v=6m/s, \\ m\text{'}=30kg,v\text{'}=0m/s \\ conservethemomentum,letthecommonvelocitybec \\ mv+m\text{'}v\text{'}=50c \\ c=\frac{120}{50}=\frac{12}{5}m/s \\ Regards \end{gathered}$$