Conservation of mechanical energy

Question

Is the mechanical energy after the collision conserved or not conserved? Explain.

Answer 1

Using conservation of energy, you can determine the speeds of both carts immediately before the collision by setting the initial gravitational potential energy equal to the kinetic energy at the bottom of their respective ramps.

Once you have both of those speeds, you can used the fact that momentum is conserved to find the final speed of the combined carts.

Having both initial speeds and the single final speed, calculating the change of kinetic energy is straightforward. If the change is zero, then the mechanical energy is conserved, if it is not, then some mechanical energy was lost during the collision.

HINT: When two objects stick together after a collision, they ALWAYS exhibit the same conservation behavior. In other words, the act of sticking together either: ALWAYS conserves mechanical energy, or NEVER conserves mechanical energy. Your answer to the above work will tell you which one it is.

Good luck!!