Understanding Energy Conservation: Analyzing Missing Energy in a Ball's Motion

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In summary: When the rubber ball rolls, it creates a small amount of heat energy due to friction with the surface it's rolling on, whereas the steel ball would create a different type of energy due to its different material and the surface it's rolling on.In summary, the conversation discusses the concept of total energy conservation and the missing energy in an experiment involving a ball rolling down a slope. Hints are given to consider factors such as gravity, mass, friction, and energy conversion through sound. The conversation also mentions the different behaviors of a rubber ball and a steel ball on a track and how they can affect the results. Further data is offered for a more thorough analysis.
  • #1
ReoFonzo
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Okay here is my question.:shy:

If Total Energy should be constant, because the loss in Potention energy should equal a gain in Kinetic Energy, where does the missing total energy go to ?

Here is my data;
TOTAL ENERGY: MISSING ENERGY:
.1254 .00132
.1236 .00103
.1239 .00106
.11883 .0062
.1241 .00085
.1049 .02007
.12254 .00246
.1189 .00608
.1153 .00961
.1191 .00586
.10509 .0191

To obtain my missing energy I took the highess total energy which is the top of the pattern, .1254 MINUS the other results to obtain my missing energy.

DESCRIPTION: In our lab we used a ball and let it accelerate down a slope that starts high, goes DOWN and back UP with a smaller height and goes back down.

MY question is: If Total Energy should be constant, because the loss in Potention energy should equal a gain in Kinetic Energy, where does the missing total energy go to ?

HERE is some hints that our teacher gave us to get through the question

A) Where is the ball missing the least amount of energy? Why ?

B) How else is the ball using energy ?

C) If friction only creates heat in kinetic mode does friction created heat account for the missing energy ?

D) Is the ball missing more and more energy from one end of the track to the other how can it get energy back once its gone ?

Really hope you can help, if you need further data just let me know I can provide some more including the height from which we drop the ball from, the balls mass, speed and time through photogates from the stop.

Thank you. :approve:
 
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  • #2
Hint #1 -- How would the results be different if this experiment were done on the moon?

Hint #2 -- How would the results be different for a steel ball on a steel track, versus a soft rubber ball on a steel track?
 
  • #3
Well in the moon wouldn't the speed be constant no matter what ?

And a steel ball... dosen't it depend on its mass... I mean shouldn't it have more PE to convert to KE then the rubber ball?

AM I right or does this make total nonsense lol ?
 
  • #4
ReoFonzo said:
Well in the moon wouldn't the speed be constant no matter what ?
Why do you say that? You are correct in one sense, but maybe not in all cases.

ReoFonzo said:
And a steel ball... dosen't it depend on its mass... I mean shouldn't it have more PE to convert to KE then the rubber ball?

I wasn't referring to the difference in mass directly. What else is different about how a rubber ball rolls as opposed to a steel ball?
 
  • #5
berkeman said:
Why do you say that? You are correct in one sense, but maybe not in all cases.



I wasn't referring to the difference in mass directly. What else is different about how a rubber ball rolls as opposed to a steel ball?

Different friction between 2 objets maybe ? IDK lol :S! :cry:
 
  • #6
Last hint -- What makes the sound as a ball rolls down the track? And do the rubber ball and steel ball make different sounds?

There are at least 3 effects that I've hinted at. Think more about the hints, and see if you can come up with all 3.
 
  • #7
berkeman said:
Last hint -- What makes the sound as a ball rolls down the track? And do the rubber ball and steel ball make different sounds?

There are at least 3 effects that I've hinted at. Think more about the hints, and see if you can come up with all 3.

OK, :confused:

Don't give up on me, here's my try.

1) I think on the moon, if there was no force applied on the ball, it would move slower because the gravity is lower than Earth ?

2) A steel ball has greater acceleration than the rubber because they have different friction.

3) REALLY I can't think of anything about the sounds because its my 1st year at an english school and I'm french and I really am struggling in physics so my guess is that a steel ball has more potentional energy because of its width.

Yeah its all nonsense, I have to get back to my english homework, hopefully you can give me an easier hint. :yuck:
 
  • #8
1) No, that's not what I'm talking about. What else is different about the moon, other than the 1/6 gravity?

2) No, assume that they both have enough friction on the ramp so that they do not slip. What is the main difference between steel and rubber (other than mass density)?

3) What is sound?
 
  • #9
I really don't know, we haven't worked with sound yet... I'd say steel surface is different than rubber... :S
 
  • #10
  • #11
Wait, sound dosen't produce by itself... it must have something to make it happend... wouldn't that something be kinetic energy ? WHICH would explain why there is missing energy ! IS that it!?
 
  • #12
ReoFonzo said:
Wait, sound dosen't produce by itself... it must have something to make it happend... wouldn't that something be kinetic energy ? WHICH would explain why there is missing energy ! IS that it!?

That's part of it. Now what about 2) and 1) in my hints in Post #8?
 
  • #13
1) No, that's not what I'm talking about. What else is different about the moon, other than the 1/6 gravity?
Its lighter
2) No, assume that they both have enough friction on the ramp so that they do not slip. What is the main difference between steel and rubber (other than mass density)?
Steel is harder and rubber is softer
3) What is sound?
Already got this one!
 
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  • #14
1) No. Let's try this another way. What if you did the rolling ball experiment under water?

2) Yes! So what happens to the shape of the softer ball when it rolls? What does that mean in terms of how much energy gets converted into ______?
 
  • #15
1)Well depending on steel's density, it would either find itself at the botom of water or float to the top without even following the pattern

2)Friction ?
 
  • #16
ReoFonzo said:
1)Well depending on steel's density, it would either find itself at the botom of water or float to the top without even following the pattern

2)Friction ?

1) No! :grumpy: Assume the dang steel ball is denser than water. When you do the experiment under water, does the steel ball accelerate faster or slower than in air (or on the moon)? Why?

2) No. Modified hint -- which rolls more easily: a car tire that is properly inflated, or an underinflated tire? Why? What is important about the "more easily" part?
 
  • #17
1) Slower, because the water makes it hard to accelerate which I don't know how to explain

2) The car tire that is properly inflated because... AIR!
 
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  • #18
ReoFonzo said:
1) Slower, because the water makes it hard to accelerate which I don't know how to explain

2) The car tire that is properly inflated because... AIR!

1) Why does a dog's face look funny when it sticks its head out the window of a moving car. And don't just say "air" What ABOUT air?!
 
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  • #19
Could you provide us with a little bit more information about the experiment please?

1. Do the track form one continuous curve from one side to the other (maybe something like a section of a circle)?

2. Did you release the ball at different heights on the same curved track?

3. Did you release the ball out of rest?

4. Is the total energy of the ball its potential energy at point of release?

5. How did you determine the missing energy?
 

1. What is energy conservation and why is it important?

Energy conservation is the principle that energy cannot be created or destroyed, only transformed from one form to another. It is important because it helps us understand how energy behaves in different systems and allows us to make more efficient use of energy resources.

2. What is missing energy in a ball's motion and how is it analyzed?

Missing energy in a ball's motion refers to the energy that is not accounted for in the ball's total energy at any given time. It can be analyzed by looking at the forces acting on the ball, such as gravity and air resistance, and calculating the work done by these forces to determine the change in the ball's energy.

3. How do different surfaces affect the conservation of energy in a ball's motion?

Different surfaces can affect the conservation of energy in a ball's motion by changing the amount of friction acting on the ball. Friction converts some of the ball's energy into heat, causing it to lose energy and slow down. Smooth surfaces will have less friction, resulting in less energy loss compared to rough surfaces.

4. Can energy be completely conserved in a ball's motion?

No, energy cannot be completely conserved in a ball's motion. Some energy will always be lost due to external factors, such as friction and air resistance. However, we can make the conservation of energy more efficient by reducing these external factors.

5. How does the conservation of energy apply to real-world situations?

The conservation of energy applies to all real-world situations involving energy, from the movement of objects to the operation of machines and the production of electricity. By understanding how energy is conserved and transformed, we can make more informed decisions about energy usage and sustainability.

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