Wrok-energy vs, Impulse-momentum

Work-energy


The work-energy theorem deals with kinetic and potential energy. Kinetic energy is equal to, 0.5mv^2, the difference in kinetic energy between two points is equal to the total work done. Another way in which to keep track of energy transfer is with potential energy. The difference in potential energy is equal to, mgh, I like to think of potential energy as the equal but opposite form of kinetic. The differences in these quantities is equal to the total work done. Work is a force that has been applied over a distance of space.

W=FD=K
*This equation holds for any total system. (K is the difference in the kinetic energy at two points)

Impulse-momentum

Impulse is equal to a force applied over an interval of time, i=ft, the impulse is in turn equal to the difference in momentum, p=mv. One thing to take notice of is that kinetic energy is equal to the velocity integral of momentum. Impulse-momentum is very useful for collisions. Momentum for a system is conserved during a collision, but the kinetic energy isn't ALWAYS conserved. It depends on the collision type.

Thanks for reading this Saturday's Concept :-)