How Much Does the Caboose Weigh After a Collision?

[alaajassar]

Freight Car-Caboose Collision

Hi, I'm a new user here. i need a help with this question:

A 29000-kg railroad freight car collides with a stationary caboose car. They couple together, and 25 percent of the initial kinetic energy is dissipated as heat, sound, vibrations, and so on. What is the mass of the caboose?

 

[tiny-tim]

Welcome to PF!

Hi alaajassar! Welcome to PF!

Call the initial velocity u, and the final velocity v, and use conservation of momentum.

What do you get? ​