Average Net Force: Kinetic Energy & Momentum

AI Thread Summary
The discussion centers on calculating average net force using two different methods: energy and momentum. For average force over distance, the change in kinetic energy divided by distance is used, following the work-energy principle. Conversely, for average force over time, the change in momentum divided by total time is applied. Participants clarify that "average" can be misleading, as it does not involve simply adding the two values. Understanding these distinctions is crucial for accurate calculations in physics.
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This is just a general question- Given a beginning and ending velocity, and distance that the object travels, would the average net force be the change in kinetic energy divided by the distance? (Using energy methods only)
I think I've also seen avg force calculated with momentum...
 
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There are (at least) two sorts of average you can take:

If you want to calculate a force averaged over *distance*, you can use the change in kinetic energy, divided by distance: Work =\delta E=F_average * d

If you want to calculate an average over *time*, then that would be given by the change in momentum, divided by the total time: impulse=\delta P= F_average * T
 
so Kef-Kei/d right?
 
Yeah.
 
ah i see- "average" is really misleading b/c u don't add the two numbers..
thanks!
 

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