Find height of ball rotating in cone without falling down?

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Homework Help Overview

The discussion revolves around a physics problem involving a ball rotating inside a cone and the determination of its height without falling. The subject area includes concepts of forces, circular motion, and potentially trigonometry.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants express confusion regarding the lack of an angle for the normal force and the implications for the forces acting on the ball. There are attempts to analyze the components of forces and the conditions for equilibrium. One participant mentions using the tangent inverse function to find an angle, while another questions the consistency of the problem statement with the given values.

Discussion Status

Some participants have indicated they have resolved parts of the problem, while others are still seeking clarification on specific aspects. There is a recognition of potential inconsistencies in the problem statement that may affect the interpretation of the results.

Contextual Notes

There is mention of partial credit received for the solution, suggesting that the problem may have specific grading criteria or expectations that are not fully met. Additionally, the height and speed values provided in the problem statement are noted as potentially inconsistent.

isukatphysics69
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Homework Statement


circlemotion.PNG


Homework Equations



f=ma
v^2/r

The Attempt at a Solution


I am confused about this question because i am not given an angle theta for the normal force on the ball.
My x component has only the normal force, my y component has only the gravitational force.
I set my y component to 0 (because the ball would be going neither up or down) and just get -mg = 0
So i am confused here on what to do. Need a hint
 

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ok i figured it out, i had to take the tan inverse to find the angle. i didn't think it through enough so the height was .15meters, i still do not know why i am only getting partial credit (0.90/1.00) for the top question
 
Ok i actually figured out the top one too i will mark solved now
 
isukatphysics69 said:
ok i figured it out, i had to take the tan inverse to find the angle. i didn't think it through enough so the height was .15meters, i still do not know why i am only getting partial credit (0.90/1.00) for the top question
You have the correct answer for the second part. I think there is something wrong in the problem statement for the first part. Notice that it says the height is .5m and the speed is 1.2m/s. This is inconsistent with the answer for the second part.
 
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