Is mechanical energy conservative?

AI Thread Summary
Mechanical energy is not inherently conservative; it can be conserved under certain conditions, such as in a frictionless environment. When friction is present, mechanical energy is not conserved due to the non-conservative nature of the frictional force. The discussion highlights that mechanical energy is a classification of energy types, not a force itself. Observing no change in kinetic energy does not necessarily indicate that energy is not conserved, as other factors may be at play. Understanding the distinction between conservative and non-conservative forces is crucial in analyzing mechanical energy in different scenarios.
UrbanXrisis
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is mechanical energy conservative?
 
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No, the mechanical energy of a system might, occasionally be conserved; "conservative"/non-conservative is a way to classify FORCES.
 
I assume you mean: Is mechanical energy conserved? Answer: Sometimes! :smile:

For example: A block sliding down a frictionless incline--mechanical energy (PE + KE) is conserved; but introduce friction, then mechanical energy is not conserved.

Did you have a particular situation in mind?
 
sliding a block on a flat table. I saw that there wasn't a change in Kinetic Energy. So, that means energy is not conserved. I know that the friction force is non-conservative but I wasn't sure about the mechanical energy.
 
UrbanXrisis said:
sliding a block on a flat table. I saw that there wasn't a change in Kinetic Energy. So, that means energy is not conserved.
Why would seeing the KE not change lead you to think that energy was not conserved? :confused:

I know that the friction force is non-conservative but I wasn't sure about the mechanical energy.
Mechanical energy is not a force.
 

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