Can someone explain this Energy Problem

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Discussion Overview

The discussion revolves around the concept of total mechanical energy and its relation to work done by other forces, particularly in the context of a spring mechanism and the work-energy theorem. Participants explore how energy is conserved or lost in different scenarios, including frictionless conditions and varying masses.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant expresses confusion about when to apply the equation Wother = E2 - E1, particularly in relation to frictionless scenarios where energy conservation is expected.
  • Another participant poses a hypothetical question about the ability of a small spring to launch a ten-tonne truck as high as a marble, suggesting a comparison of energy outputs.
  • Participants discuss the work-energy theorem and its application, with one suggesting the calculation of height reached by different masses using the equation .5kx^2 = mgh.
  • There is a reiteration of the relationship between mass and height, questioning whether an increase in mass results in a decrease in height, and a participant confirms the equation used is correct.

Areas of Agreement / Disagreement

The discussion reflects a lack of consensus on the application of the work-energy theorem and the implications of mass on height in energy transfer scenarios. Participants are exploring these concepts without reaching a definitive agreement.

Contextual Notes

Participants are navigating assumptions related to energy conservation in frictionless systems and the implications of varying mass on energy outcomes. There are unresolved mathematical steps and dependencies on definitions that are not fully clarified.

Lori
So- I'm going to confused with the concept of total mechanical energy that's loss due to work other. I provided an example below.

When do I apply this equation of Wother=E2-E2? I get confused cause I thought frictionless meant that energy is conserved.
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Would you expect a small spring to be able to fire a ten-tonne truck as high as a marble?
 
PeroK said:
Would you expect a small spring to be able to fire a ten-tonne truck as high as a marble?
I know that, but I want to understand it with the work energy theorem. I don't really understand it.
 
Lori said:
I know that, but I want to understand it with the work energy theorem. I don't really understand it.

Why not calculate the height both blocks reach?
 
PeroK said:
Why not calculate the height both blocks reach?
Is it .5kx^2 = mgh so h= kx^2 / 2mg

So when mass increases, height decreases?

Did i get the equation right ?
 
Lori said:
Is it .5kx^2 = mgh so h= kx^2 / 2mg

So when mass increases, height decreases?

Did i get the equation right ?

Yes, that's it.
 

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