Conservation of Kinetic Energy During Collision

AI Thread Summary
The discussion revolves around understanding the conservation of kinetic energy during collisions. Participants clarify the approach to calculating kinetic energy by emphasizing the importance of determining both initial and final kinetic energy values. It is highlighted that to find the change in energy, one must subtract the initial kinetic energy from the final kinetic energy. The rationale behind this method is explained, noting that a positive change indicates a gain in energy. Overall, the conversation focuses on the correct application of kinetic energy formulas and the significance of understanding energy changes in collisions.
mohabitar
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For number 3, I don't really know how to approach it. Nothing in my notes that covers such a thing. I tried using K=1/2MV^2, but that's not it. Any ideas?
 
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mohabitar said:
I tried using K=1/2MV^2, but that's not it. Any ideas?
What do you mean "that's not it"? Did you calculate the initial and final kinetic energy?
 
Ohh, duh! So subtract the final kinetic from initial kinetic. Well actually it turned out that we subtract initial from final, why do we do that rather than final from initial? (how do we know whether it lost or gained energy)
 
Change always means final minus initial. If the change is positive, then you've gained energy. (Is that likely?)
 

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