Six diesel units in series can provide 13.4MW of power to the lead car of a frei
ID: 1903126 • Letter: S
Question
Six diesel units in series can provide 13.4MW of power to the lead car of a freight train. The diesel units have total mass 1.10times 10^6 kg. The average car in the train has mass 8.2 times 10^4 kg and requires a horizontal pull of 2.8kN to move at a constant 27m/s on level tracks. A- This would leave no power for accelerating or climbing hills. Show that the extra force needed to accelerate the train is about the same for a 0.10 m m/s^2 acceleration or a 1.0% slope (slope angle lpha =arctan 0.010). B- With the 1.0% slope, show that an extra 2.9 { m MW} of power is needed to maintain the 27 m m/s speed of the diesel units.Explanation / Answer
Six diesel units in series can provide 13.4MW of power to the lead car of a freight train. The diesel units have total mass of 1.1*10^6 kg. The average car in the train has mass 8.2*10^4 kg and requires a horizontal pull of 2.8kN to move at a constant 27m/s on level tracks. How many cars can be in the train under these conditions? Everytime I try to figure it out, I get 4.3 cars as my answer but the correct answer is 177. How do I solve this problem? the power required for each train is p = F v = 2800 x 27 = 75600 watt so that number of cars N = total power / power of each car = P / p = 13400000 / 75600 = 177.25 = 177 (nearly) that's it.