I have a physics lab to do. Now, I want to make sure that I am on the right track (I don't want to go completely in the wrong direction). Essentially what we have for our lab is two cans of soup (both with the same dimensions and similar mass) which we roll down a ramp and let it roll until it stops. The objective is to determine which will one go farther and why it does so. The biggest difference between the two is the contents. In one of them, we have a broth (very thin and liquidy) and in the other creme of chicken soup (very creamy and thick).(adsbygoogle = window.adsbygoogle || []).push({});

Now, my hypothesis is that the creme of chicken soup will go farther. The can has two kinds of kinetic energy (rotational and translational). Is if safe for me to assume that the creme of chicken soup willhave more rotatioanl kinetic energy than the broth because more energy is needed to get it rotating? That being true is the basis for my hypothesis.

The can only slows down and stops because of friction. Another assumption im making is that friction has a greater effect on translational motion than it does on rotational. This assumption seems a little more valid than the other one. Is it also true? a fair estimate? or completely wrong?

If my two assumptions are true, than i can say that friction will add on the two cans in a very similar fashion. However, when one of the cans runs out of translational kinetic energy it will run purely on rotational kinetic energy. Thus the can with greater rotational kinetic energy will go farther.

This is because the two cans kinetic energy will decrease at a similar rate. However, one can will run out of translational kinetic energy before the other can. At that the net decrease in kinetic energy for it will have reduced (since friction is only acting on the rotational kinetic energy and we assumed earlier that friction has a markedly lower effect on rotational kinetic energy).

Are my assumptions correct? If they aren't dont tell me what is the correct method. I would much rather discover that on my own.

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# Homework Help: Rotational Mechanics

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