What Is the Average Force Produced by One Gallon of Gasoline?

AI Thread Summary
One gallon of gasoline contains 3.1 x 10^7 calories of potential energy, which can propel a car over a distance of 25 miles. The average force produced by this gasoline can be calculated by converting calories to Joules and then determining the energy per mile. The calculations yield an average force of approximately 3220.8 N. The discussion highlights confusion regarding the relationship between energy, force, and distance, emphasizing the need to apply the work formula effectively. Ultimately, the calculations confirm that the derived average force is reasonable and aligns with the expected results.
teremala
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Homework Statement


"One gallon of gasoline contains 3.1*10^7 calories of potential energy that are released during combustion. If 1 gal of gasoline can provide the force that moves a car through a displacement of 25 mi, what is the average force produced by the gasoline?"

Homework Equations


This is where I am confused. All of the equations I can think of for average force require velocities, mass, time, etc. and I don't see how to get from here to there. Right now I am just using 1 cal = 4.18 Joules and 1 mi = 1609.3 m.

The Attempt at a Solution


Assuming complete efficiency,
3.1*10^7 cal / 25 mi = 1.24 * 10^6 cal / mi
then multiply that by 4.18 Joules/1 cal and by 1 mi/1609.3 m to get 3220.8 J/m (or N).

This could of course be multiplied back out to "work", but that strikes strikes me as circular. I just don't know if the answer I have is reasonable/what the question wants, since it's flagged as difficult and I haven't done anything but convert units. What am I missing?
 
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See what you can do with: work = force * distance.
 
Thanks, that was what the professor said too. As far as I can tell though work=f*d was already accounted for when I averaged calories/mile. In any case, this was the correct answer.
 
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