Natural vibration - energy method

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Discussion Overview

The discussion revolves around a homework problem related to natural vibration and the energy method, specifically focusing on parts d and e of the problem statement. Participants are seeking clarification and validation of their approaches to calculating kinetic energy and potential energy in the context of the problem.

Discussion Character

  • Homework-related

Main Points Raised

  • One participant presents their calculations for part d, expressing that their total kinetic energy formula is 0.5I*(omega^2) + 0.5*m*(r*theta^2+(4r/3pi)^2).
  • The same participant proposes a potential energy expression for part e as mgR(theta.sintheta + costheta - 1).
  • Another participant questions the correctness of the first participant's earlier question regarding part 3, indicating some uncertainty in the problem's parts.
  • The initial poster expresses confusion about their answers for parts d and e, indicating a lack of confidence in their calculations.

Areas of Agreement / Disagreement

The discussion remains unresolved, with no consensus on the correctness of the proposed answers for parts d and e. Participants express uncertainty and seek clarification.

Contextual Notes

There are indications of confusion regarding the problem parts, and the initial poster has not provided complete working for their calculations, which may limit the ability to assess the correctness of their answers.

luznyr
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Homework Statement



the problem is in the attached file, I am having trouble with part d and e. cheers. [the answer for B is mr^2(0.5-16/9pi^2)]

Homework Equations





The Attempt at a Solution



i won't upload all my working as i have stuff everywhere but for part d:

i got my answer as 0.5I*(omega^2) + 0.5*m*(r*theta^2+(4r/3pi)^2), using the formula for total kinetic energy as 0.5Iomega^2+0.5mv^2

and part e: mgR(theta.sintheta + costheta - 1)

are these along the right tracks?
 

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are you sure your question 3 is correct?
 
im not too sure what you mean question three sorry, if by part C, then I'm not too concerned about that for the moment, just part D and E
 
sorry... i mean D
 
i have no idea if either of my answers for d or e are right, hence why i stuck it on here...im just so confused haha
 

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