Final velocity = 16.33 m/s
Explanations:[tex]\begin{gathered} \text{Mass of car A, M}_A=\text{ 2000kg} \\ \text{Mass of car B, M}_B=\text{ 1000kg} \end{gathered}[/tex][tex]\begin{gathered} \text{Initial sp}eedofcarA,U_A=\text{ 15.0 m/s} \\ \text{Initial sp}eedofcarB,U_B=\text{ 19.0 m/s} \end{gathered}[/tex]When cars A and B collide, they will start moving at a constant velocity, V
According to the law of conservation of momentum:
[tex]M_AU_A+M_BU_B=(M_A+M_B)V_{}[/tex]where V represents the final velocity when the two cars stick together
Substitute these values into the given equation
[tex]\begin{gathered} 2000(15)\text{ + 1000(19) = }(2000+1000)V \\ 30000+19000\text{ = 3000V} \\ 49000\text{ = 3000V} \\ V\text{ = }\frac{49000}{3000} \\ V\text{ = }16.33\text{ m/s} \end{gathered}[/tex]