Where did I go wrong in deriving potential energy?

AI Thread Summary
The discussion centers on deriving elastic energy and the confusion surrounding the negative sign in the work calculation. It clarifies that potential energy is defined as the negative of the work done by a force when moving an object. The elastic energy, a form of potential energy, is calculated using the work done by the elastic force between two points. The correct expression for this relationship is given as -(U2-U1). Understanding these principles is crucial for accurately deriving elastic energy.
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Hello, i am trying to derive flexible energy, but i get a negative sign in front of a Work (A). Where did i miss?
F is force of a spring. I don't know if i used Hooke's law correctly...

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Thank you for looking.
 
Last edited:
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rcgldr said:
Nomrally, potential energy is the negative of the work performed by some force in moving some object from one point to another.

http://en.wikipedia.org/wiki/Potential_energy


I am sorry i miss write... it is about flexible energy :)
 
I think you mean "elastic energy". And the elastic energy is a form of potential energy.
What you calculate is the work done by the elastic force between the points 1 and 2. This is equal to -(U2-U1).
 

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