Calculating Tractive Effort At Speeds

[alphareign]

How does one calculate the tractive effort of a locomotive at various speeds? Is there a formula for this?

 

[jack action]

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

F_t = \frac{P}{v}​

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):

F_t = \mu N​

Where \mu is the coefficient of friction and N is the normal force acting on the wheels.

 

[alphareign]

Thank you so much.