Power Problem: Calculating the Power Required to Push a Train Up an Incline

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To calculate the power required to push a train weighing 110,000 kilograms up a 1 in 100 incline at 20 kilometers per hour, the relevant power equation is P = Force times velocity. The force can be determined using equilibrium considerations, where the gravitational force component acting along the incline is calculated. The incline ratio of 1 in 100 translates to a height gain of 1 meter for every 100 meters traveled horizontally. The power calculation involves determining the force from the weight of the train and the incline, then multiplying by the train's velocity. The discussion emphasizes the need to express the incline ratio correctly and calculate the time taken to reach a specific height for accurate power determination.
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Homework Statement



What power is required to push a train weighing 110,000 kilograms up an incline of 1 in 100 at 20 kilometers per hour, all frictional resistances being neglected?

Homework Equations


P = ΔE/ ΔT


The Attempt at a Solution



This is the only power equation we discussed:
P= ΔE/ ΔT = (m)(g)(h)/t
This doesn't really fit with the data given b/c there's a velocity. Also
I don't know how to express that ratio of 1 in 100 in the equation.
 
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adk said:

Homework Statement



What power is required to push a train weighing 110,000 kilograms up an incline of 1 in 100 at 20 kilometers per hour, all frictional resistances being neglected?

Homework Equations


P = ΔE/ ΔT


The Attempt at a Solution



This is the only power equation we discussed:
P= ΔE/ ΔT = (m)(g)(h)/t
This doesn't really fit with the data given b/c there's a velocity. Also
I don't know how to express that ratio of 1 in 100 in the equation.
the power required to push the train at constant speed may be determined from Power = Force times velocity, where the force is the pushing force which you can calculate from equilibrium considerations. Or you can calculate that force and use P= work/time, where work is the pushing force times the distance traveled in the direction of the force (letting h=1 m, find the distance traveled up the incline to reach the 1 m high mark using the 1:100 slope), then you can calculate the time it takes for the train to reach a point 1 m high using kinematics. Or else use your listed equation, finding t in the same manner...it all leads to the same answer.
 
PhanthomJay said:
the power required to push the train at constant speed may be determined from Power = Force times velocity, where the force is the pushing force which you can calculate from equilibrium considerations.

If we use the first equation:

F=m*a = (110,000)(9.81) = 1079100
P=1079100*20km/hr=21582000 N

Is this correct? Where do you go from here?
 
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