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