Physics Lab on Cans & Liquids

[Solaxys]

1. Homework Statement
You are given two cans to roll down a 1m ramp at angle 15 degrees [and then at 30 degrees for a check].
Can A has a less viscous fluid, broth.
Can B has a more viscous fluid, cream of mushroom soup.

Now through constant experimentation we find that, can B rolls down the ramp and ends up further than A, even though A accelerates much faster than B down the ramp.
Why?
And, what is the pathway of energy [where energy goes from X to 0, where X is the initial energy of both cans at the top of the ramp]

2. Homework Equations
GPE : mgh
Linear KE: 0.5mv^2
Angular KE: 0.5Iw^2
[Whatever else applies]

3. The Attempt at a Solution
For the why, a theory is devised:
Neglecting friction, and gravitational force due to the can's having the same mass, and the liquid's mass having a difference of less than 1%, we look into just the Kinetic energies.

We can choose two extremes to represent the viscosity: water[A] and honey.
Therefore, since this is a blackbody problem we can only assume, that the liquid in A remains at the bottom and thus linear. However, the liquid in B is more viscous, therefore it rolls with the can to a certain extent, or at least more than the low visous water.

This means, by the end of the ramp, we can assume that A has more linear kinetic energy, while B has more angular kinetic energy, for the reasons above.

And through various trials, it was seen that linear kinetic energy is easier to diminish than angular kinetic energy. Therefore, Can B rolls further than Can A, even though Can A moves faster down the ramp.

This is a theory, and we [my lab group and I] could use some feedback/comments/questions/concerns/la di da.


As for the energy pathway.
We don't want to draw the entire thing here, but just raise some points.
Firstly, the energies we see affecting the cans are:
Potential Energy [Gravitational], Kinetic Energy, Energy Loss due to Friction, Energy Loss due to Drag.
Is there any other energy we are missing?

Any ideas how we can show, via data, how these are lost/spent/gained throughout the lab?


Thank you for your help =).

 

[Jhero]

Thank you for sharing your experiment and theory with us. I am always interested in understanding the underlying principles behind observations and data.

Based on your description, it seems like you have a good understanding of the factors that could affect the movement of the cans down the ramp. I agree with your theory that the difference in viscosity between the two liquids plays a key role in the final position of the cans at the end of the ramp.

To further support your theory, I suggest conducting additional experiments using liquids with different viscosities to see if the trend holds. This will help to strengthen your findings and provide more evidence for your theory.

As for the energy pathway, you have identified the main forms of energy involved in the experiment. To show how these energies are lost or gained throughout the lab, you could track the changes in potential and kinetic energies at different points along the ramp. This could be done by measuring the height and velocity of the cans at different points and using the equations you have listed to calculate the energies.

Additionally, you could also consider measuring the temperature of the liquids before and after the experiment to see if there is any change in thermal energy. This could be an interesting factor to include in your analysis.

Overall, I think you have a solid theory and it would be great to see more data and experimentation to support it. Keep up the good work and don't hesitate to reach out for any further feedback or assistance.

Best of luck with your research!
Scientist