posted by Anonymous .
A 12100 kg railroad car travels alone on a level frictionless track with a constant speed of 20.5 m/s. A 5850 kg load, initially at rest, is dropped onto the car. What will be the car's new speed?
An application of the law of conservation of linear momentum, in the horizontal direction, will tell you the answer.
Give it a try.
Adding a load by dropping from above will not change the horizontal momentum.
umm, im sorry about that answer, but really? 131 thousand meters per second? might want to check your math there, that's 131 kilometers per second which is pretty fast...