PHY221 Ch7: W and KE 1.Recall main points: Work Energy Theorem Understand the derivation of the work energy theorem Know how to compute the work of a given force over an arbitrary displacement: Understand the meaning W= and how to apply it. Know how to compute W for weight, spring force and gravity 2.Discussion and examples

PHY221 Ch7: W and KE 1. Main Points Work Energy theorem in 3D with dot product: General Case Dot product in 2 dim, magnitude angle: Dot product in 2 dim, component definition: Dot product in 3 dim, component definition:

PHY221 Ch7: W and KE 1. Main Points Work Energy theorem derivation; 3 dim general case (learn this)

PHY221 Ch7: W and KE 1. Main Points Work Energy theorem derivation; 3 dim general case (learn this)

PHY221 Ch7: W and KE 2. Main Points Example UCM:Example 1Dim motion under constant force:

PHY221 Ch7: W and KE 1. Main Points Example of Computation of W: W for weight:

PHY221 Ch7: W and KE 1. Main Points Example of Computation of W: W for a Spring force:

PHY221 Ch7: W and KE 1. Main Points Example of Computation of W: W for Gravity:

PHY221 Ch7: W and KE 1. Main Points Example of use: Block down incline: get velocity at bottom:

Ch.7 W and KE: Practice problems & Exercises