Undergrad Can someone explain this Energy Problem

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The discussion revolves around the confusion regarding the concept of total mechanical energy loss due to work done by other forces, specifically in the context of the work-energy theorem. Participants clarify that while energy is conserved in frictionless scenarios, the application of the equation Wother = E2 - E1 is essential for understanding energy transformations. The example of a small spring firing a ten-tonne truck raises questions about the relationship between mass and height achieved, leading to the derivation of the equation h = kx^2 / 2mg. It is confirmed that as mass increases, the height reached decreases, illustrating the inverse relationship between mass and height in this context. Overall, the discussion emphasizes the importance of correctly applying the work-energy theorem to analyze mechanical energy in various scenarios.
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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