A railroad car with a mass of 2.33 × 104 kg moving at 3.71 m/s collides and joins with two railroad cars already joined together, each with the same mass as the single car and initially moving in the same direction at 1.44 m/s.What is the final speed of the three joined cars after the collision?

Question

A railroad car with a mass of 2.33 × 104 kg moving at 3.71 m/s collides and joins with two railroad cars already joined together, each with the same mass as the single car and initially moving in the same direction at 1.44 m/s.What is the final speed of the three joined cars after the collision?
Answer in units of m/s.

bobpursley · Answer

conservation of momentum initial momentum=finalmomentum 2.33E4*3.71+(2*2.33E4)( 1.44)=2.33E4*3V or 3.71+2.88=3v solve for V