15 points! a freight train is being assembled in a switching yard. car 1 has a mass of 65,000 kg and moves with a velocity of +0.80m/s. car 2 with a mass of 92,000 kg and has a velocity of +1.3m/s overtakes car 1 and couples to it. neglecting friction, calculate the final velocity of the two cars after they become coupled.

solve using conservation of momentum.

An ideal otto cycle has a compression ratio of 8. at the beginning of the compression process, air is at 95 kpa and 27°c, and 750 kj/kg of heat is transferred to air during the constant-volume heat-addition process. assuming constant specific heats at room temperature, determine (a) the pressure and temperature at the end of the heat-addition process, (b) the net work output, (c) the thermal efficiency, and (d) the mean effective pressure for the cycle. (4390 kpa, 1730 k; 423 kj/kg; 56.4%; 534 kpa)