14. A 10,000 kg box car sits at rest on a train track. A 20,000 kg timber car travels west at 1.5 m/s and collides with the empty box car. At the exact same time, a third train car collides with the other end of the box car. This third car is a 14, 000 kg freight car moving at 4 m/s east. If all three cars stick together

8.29 two streams containing pyridine and acetic acid at 25°c are mixed and fed into a heat exchanger. due to the heat-of-mixing effect, it is desired to reduce the temperature after mixing to 25°c using a stream of chilled ethylene glycol as indicated in the diagram. calculate the mass flow rate of ethylene glycol needed. the heat capacity of ethylene glycol at these conditions is approximately 2.8 kj/(kg k), and the enthalpy change of mixing (δmixh) is given below.