Acceleration ball rolling on a parabola

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Discussion Overview

The discussion revolves around finding the acceleration of a ball rolling down a parabola, with the intention of deriving its parametric equation over time. Participants explore the implications of different forms of the parabola and the effects of gravity while considering the relationship to the Brachistochrone problem.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant seeks guidance on how to find the acceleration of a ball rolling down a parabola, indicating prior unsuccessful attempts.
  • Another participant asks clarifying questions about the parabola's equation, the consideration of rotational kinetic energy, and the radius of the ball.
  • Further clarification reveals that the equation of the parabola is variable, and the participant is focused on a general solution while ignoring factors other than gravity.
  • A participant expresses a need to code an animation in Maple to visualize the ball rolling down multiple parabolas and a straight line, aiming to determine the fastest path between two points.
  • Reference is made to the Brachistochrone problem, with one participant noting their familiarity with it and its relation to the current discussion.
  • Another participant mentions having previously solved the cycloid related to the Brachistochrone problem and expresses a need for further knowledge regarding the parabola.

Areas of Agreement / Disagreement

Participants generally agree on the relevance of the Brachistochrone problem to the discussion, but multiple competing views and uncertainties remain regarding the specifics of the parabola and the approach to solving the problem.

Contextual Notes

Participants have not provided specific assumptions about the parabola's orientation or the exact form of the equation, leading to potential limitations in the discussion.

Barioth
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Hi, I'm trying to find the Acceleration of a ball rolling down on a parabola.


If I could find it, then I could integrate it twice and find it's parametric equation given by the time.
How could I find this?
I tried a few things, but nothing that made any sense.
If someone could give me a hint on where to start it would be super!


Thanks for passing by!
 
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A couple of questions:

1. Do you have the equation for the parabola?

2. Are you ignoring rotational kinetic energy or not?

3. What is the radius of the ball?
 
Sorry I should have given more information!

1- The equation is given but is variating, so I have to find a solution for its general form.

2- We're ignoring pretty much everything except gravity.

3-Since we're ignoring everything the radius isn't told.
 
Barioth said:
Sorry I should have given more information!

1- The equation is given but is variating, so I have to find a solution for its general form.

2- We're ignoring pretty much everything except gravity.

3-Since we're ignoring everything the radius isn't told.

That helps, but I still don't know a few things. Is the parabola opening up? Down? What general form are you given? It might be helpful if you could state the original problem verbatim.
 
I need to code in maple an animation of a ball rolling down multiple parabola and a straight line.

To find the fastest way for a ball to move from Point A to B.
They all start at the Point (0,0) and end at (K,-1)

K is given by the user before computing. I have 2 different parabola that have some difference in their acceleration.

I've managed to evalute r(t) for the straight line, but I can't figure out how to start with the parabola.
If I have $$y=ax^2+bx+c$$ ( in my case C always equal to 0)

edit: I had guess it is opening up also.

The problem is in French and I'm doing my best to translate it, hope it sounds fine!
 
Nice call MarkFL it is indeed!

I've managed to deal with the Brachistochrone ( Well I've found some equation that I had to change a litle bit to make it work for me...), but the parabola give me problem.

I might try to go find a physics teacher in my old school, I'm having an hard time translating the question.
 
The solution to the brachistochrone (from the Greek for "shortest time") is the cycloid. To prove that requires the calculus of variations, and some technical details. Can you fit a cycloid to the points you have?
 
Hi, I have solved the cycloide already, (I had to do my semester research on cycloide 3 years ago). I can make it fit the point that are given.

I'll put the parabola on the ice and do some reading, I might need some more knowledge
now!

Thanks for Helping Ackbach!
 

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