Conservative & Non-Conservative Forces
o Conservative forces are those for which work done depends only on initial and final points . Example- Gravitational force , Electrostatic force .
o Non-Conservative forces are those where the work done or the kinetic energy did depend on other factors such as the velocity or the particular path taken by the object . Example- Frictional force .
The Conservation of Mechanical Energy o
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Mechanical Energy is the energy associated with the motion and position of an object .
The quantity K + V ( x ), is called the total mechanical energy of the system .
For a conservative force , ΔK = ΔW = F ( x ) Δx Also , - V ( x ) = F ( x ) Δx
o This employs Δ ( K + V ) = 0 for a conservative force . o
Individually the kinetic energy K and the potential energy V ( x ) may vary from point to point , but the sum is a constant .
o Conservative Force : o
A force F ( x ) is conservative if it can be derived from a scalar quantity V ( x ) by the relation : F ( x ) = - dv / dx