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Calculating Tractive Effort At Speeds

  1. Mar 5, 2015 #1
    How does one calculate the tractive effort of a locomotive at various speeds? Is there a formula for this?
  2. jcsd
  3. Mar 5, 2015 #2

    jack action

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    The tractive effort ([itex]F_t[/itex]) is simply the power available at the wheels ([itex]P[/itex]) divided by the speed of the locomotive ([itex]v[/itex]):

    [tex]F_t = \frac{P}{v}[/tex]​

    But, no matter how much power there is at the wheels, it cannot exceed the friction force between the wheels and the rails (otherwise the wheels are spinning):

    [tex]F_t = \mu N[/tex]​

    Where [itex]\mu[/itex] is the coefficient of friction and [itex]N[/itex] is the normal force acting on the wheels.
  4. Mar 5, 2015 #3
    Thank you so much.
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