Register to reply 
Quick P. Energy Derivation Question 
Share this thread: 
#1
Mar612, 08:41 PM

P: 867

When deriving the workpotential energy theorem, my book states that dV (derivative of the potential energy) is equal to the negative of Fdr without a corresponding explanation. What is the justification behind the negative sign?



#2
Mar612, 09:06 PM

P: 51

As such,there is no explanation,its about definition.
The important thing is,for conservative forces,you can define a potential.Even if you had define dV=Fdr,you would have a consistent theory.The fact that dV=Fdr,and not Fdr,is not logic,its convention. In essence,it means that,when positive work is done by the field forces on body,its potential energy decreases,and kinetic energy increases. 


Register to reply 
Related Discussions  
Just a quick question on the derivation of energy  Special & General Relativity  2  
Gravitational Potential Energy Derivation question?  Introductory Physics Homework  7  
Silly question, derivation of energy  Classical Physics  4  
Quick derivation question  Introductory Physics Homework  0  
Quick Hello Then Question About Energy  Introductory Physics Homework  1 