Gaining Insight into Energy Conservation: A New Perspective

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Discussion Overview

The discussion revolves around the concept of energy conservation, specifically exploring different perspectives on what energy is and how it can be understood in terms of forces acting on a mass. Participants examine kinetic and potential energy through integrals and the work-energy principle, while also considering the implications of reference points in energy calculations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant proposes understanding energy as the total force needed to position a mass, linking kinetic energy to acceleration and potential energy to gravitational force.
  • Another participant questions the validity of this perspective, seeking clarification on its truth.
  • A different participant affirms the initial logic, suggesting that personal insights into complex concepts are valuable and not trivial.
  • One participant points out that the initial explanation focuses on changes in energy rather than total energy, emphasizing the importance of reference points in energy calculations.
  • The original poster acknowledges the distinction between changes in energy and total energy, recognizing the role of the reference point in these calculations.

Areas of Agreement / Disagreement

Participants express varying degrees of agreement on the initial perspective of energy as related to forces, but there is no consensus on the completeness or correctness of the explanation. Some participants affirm the logic while others highlight limitations and nuances, indicating that the discussion remains unresolved.

Contextual Notes

Participants discuss the concept of energy in terms of changes rather than total energy, which may depend on initial conditions and reference points. This introduces complexity that is not fully resolved in the discussion.

Who May Find This Useful

This discussion may be of interest to those exploring foundational concepts in physics, particularly students or enthusiasts seeking to understand energy conservation and its implications in different contexts.

daniel_i_l
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I was thinking about that question (what is energy) and I realized that I could easily understand what energy is and why it is conserved if I thought of it as the total force needed to get a mass to the position that it is in. For example:

Kinetic energy - inorder to give a mass speed you need to accelerate it, the force would be F = ma, and the integral of mad(x) is m*a*x = m * a * 1/2at^2 = m * 1/2a^2t^2 = 1/2mv^2
Potential energy - F = mg (the same as KE) and the integral of mgd(x) is m*g*x (mgh) This is true for other kinds of energy too. So really the energy of a mass is simply the sum of all the forces needed to get it to the position and speed that it is in (this is why work is the change in energy). And that is why energy is always conserved if you don't add any external forces to it - cause if you don't add any force then the total force (energy)will always stay the same. (this isn't a new theory or anything, just a way of looking at things)
So, is this obvious and I'm stupid for not noticing it before , interesting but not connected to reality, enlightning...
 
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Is this true?
 
Yes, your logic is fine. No, it's not stupid or obvious. Everybody has a point in time where they figure out a way to think of it that makes complete sense to them. Congratulations:).
 
here i would like to suggest a site tell me what u think http://home.pacifier.com/~ppenn/whatis2.html
 
daniel_i_l said:
I was thinking about that question (what is energy) and I realized that I could easily understand what energy is and why it is conserved if I thought of it as the total force needed to get a mass to the position that it is in. For example:
Kinetic energy - inorder to give a mass speed you need to accelerate it, the force would be F = ma, and the integral of mad(x) is m*a*x = m * a * 1/2at^2 = m * 1/2a^2t^2 = 1/2mv^2
This will give you the change in kinetic energy, but not the total kinetic energy, since the initial velocity of the body is not considered here. m*a*x = F*x which is work - i.e. the work done by an unbalanced force accelerating a body over a distance of x is equal to the change in the body's kinetic energy. Likewise in your potential example, the work done in moving a body from one equipotential to another is equal to the change in potential energy. So just be aware that you're dealing with changes in energy, not total mechanical energy.
 
Thanks guys!
Yes, I was aware that I was only dealing with the changes - the total energy depends in were you start from, or were your referance spot is.
 

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