Two cars are travelling in the +x direction. A 1.8 x 103 kg BMW with speed 42 m/s hits the rear of a 1.2 x 103 kg VW with speed 25m/s. Neither driver applies the brakes. Ignore friction. a. If the speed of the BMW is 33 m/s just after the collision, find the speed of the VW just after the collision

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.