Physical Modeling, Fall WORK Work provides a means of determining the motion of an object when the force applied to it is known as a function of position.

Physical Modeling, Fall Work Energy Theorem W net is the work done by F net the net force acting on a body.

Physical Modeling, Fall Work Energy Theorem (continued)

Physical Modeling, Fall Work Energy Theorem (continued)

Physical Modeling, Fall Work Energy Theorem (concluded) Define Kinetic Energy Then, W net = K f - K i W net =  K

Physical Modeling, Fall WORK - GENERAL DEFINITION

Physical Modeling, Fall CONSERVATIVE FORCES A force is conservative if the work it does on a particle that moves through a closed path is zero, otherwise, the force is nonconservative.

Physical Modeling, Fall CONSERVATIVE FORCES (cont) A force is conservative if the work it does on a particle that moves between two points is the same for all paths connecting those points, otherwise, the force in nonconservative

Physical Modeling, Fall Potential Energy  U = - W c W net =  K If W net = W c Then,  K = -  U  K +  U = 0  (K + U) = 0

Physical Modeling, Fall MECHANICAL ENERGY U + K = E E = Mechanical Energy  E = 0 E i = E f K i + U i = K f + U f

Physical Modeling, Fall Mass and Spring