Forces two objects apply on each other during inelastic collision

AI Thread Summary
In an inelastic collision problem, the forces exerted between two objects can be calculated using their pre-collision velocities and the time of collision. The user calculated the force of a 2kg puck on a 3kg puck as 60N and the force of the 3kg puck on the 2kg puck as 45N, based on the formula F=m(Δv/Δt). The discussion emphasizes the relevance of pre-collision values since post-collision forces are not applicable. Newton's Third Law is highlighted, indicating that forces between the objects are equal and opposite. Understanding impulse as the change in momentum (J=Ft) is also clarified, linking it to the forces calculated.
austindubose
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Homework Statement


11mavpi.png


Values from previous problem:
Pre-collision: v2kg=6m/s -->, v3kg=3m/s <--
Post-collision: v2kg=2m/s <--, v3kg=5.67m/s -->
Collision time: 0.2 sec

Homework Equations


F=mA=m(Δv/Δt)

The Attempt at a Solution


My instinct to solve this was to use the pre-collision values to find out the forces each puck had on each other, because it seems like post-collision values for velocity would be irrelevant because the pucks are no longer having any force on each other. So, I did the following...

Force of 2kg puck on 3kg puck: F=2kg(6m/s / 0.2 sec) = 60N
Force of 3kg puck on 2kg puck: F=3kg(3m/s / 0.2 sec) = 45N

Is this the correct way to approach this problem? Thanks for your help!
 
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J = Favg*t. Also, Newton's Third Law.
 
Can you elaborate a bit on that? I'm not completely familiar with that formula. We probably just use different variables because I don't recognize the J.
 
J = magnitude of change in momentum.
 
I think watermelonpig is saying Impulse= Force(average) x Time Interval. I=Ft. I think most physics books call change in momentum, impulse, so maybe that will help. Your also given the time...
 
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