A 31,000 kg freight car is coasting at 0.900 m/s with negligible friction under a hopper that dumps 120,000 kg of scrap metal into it. (a) What is the final velocity. (in m/s) of the loaded freight car? (Enter the magnitude.) 0.2 x m/s (b) How much kinetic energy (in J) is lost? 9535 J