Conservation of Energy: Pushing Boxes

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Discussion Overview

The discussion revolves around the conservation of energy in the context of pushing boxes across a surface, exploring the energy transfer involved when overcoming friction versus when it is not overcome. It touches on theoretical aspects of energy dissipation, work done, and the implications for thermal energy in different scenarios.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions whether the energy expended while pushing a box is entirely dissipated as thermal energy when friction prevents movement.
  • Another participant asserts that energy is transferred to the ground in both scenarios, implying a connection between the box and the ground.
  • A different participant claims that if friction is not overcome, no work is done on the box, and the energy is dissipated as thermal energy within the body.
  • One participant expresses confusion about the implications of energy dissipation, suggesting that pushing an immovable object should result in greater heat generation than pushing a movable one.
  • Another participant encourages experimentation, suggesting that one would indeed feel hotter when pushing against an immovable object for an extended period.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between work done on the box and energy dissipation, with no consensus reached on the implications of pushing against friction versus moving an object.

Contextual Notes

The discussion includes assumptions about energy transfer and the definitions of work and friction, which may not be fully articulated or agreed upon by all participants.

PowerWill500
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I have a question regarding the conservation of energy. If I were to push a medium sized box across a surface, I would be imparting a certain amount of energy to it (and myself) and also dissipating a certain amount of thermal energy into the surface. This energy I'm supplying comes from the transfer of the chemically stored energy in my body when I push the box, yes?

Now, if I were to expend an equal amount of bodily energy pushing against a large box, and was not able to overcome the friction force, would all that energy be instead dissipated as thermal energy into the ground and box? Maybe I'm just overestimating the awesomeness of kinetic energy, but intuition (often wrong, admittedly) tells me that the thermal energy produced in the second scenario would not be equivalent to the kinetic and thermal energy my efforts produced in the first. Apologies for a potentially dumb question, but could someone explain this?
 
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Yes indeed, you transfer energy to ground (in both cases).
In fact u cannot push a box against a wall if the wall is not well connected to the ground.

Ll.
 
No. In the second case, since you did not overcome friction, no work was done on the box and whatever (food/chemical) energy was merely dissipated as thermal energy within your body.
 
cesiumfrog said:
No. In the second case, since you did not overcome friction, no work was done on the box and whatever (food/chemical) energy was merely dissipated as thermal energy within your body.

But if that's the case, I would get hotter pushing something that didn't move than pushing something that did, even if I was expending the same amount of energy. That doesn't make sense to me.
 
PowerWill500 said:
But if that's the case, I would get hotter pushing something that didn't move than pushing something that did, even if I was expending the same amount of energy. That doesn't make sense to me.
Why not? Try it! You will most certainly get hotter if you push hard on an immovable wall for more than a few seconds.
 

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