Work 1. Work done by a constant force in 1-D motion: costWFsFsFsφ===iGGW= Fsif the force and displacement have the same direction, W= −Fsif they have opposite directions. 2. Work done by a varying force or work done by a force in 2-D motion: tdds∫∫iGG)gyy3. Work done by gravity for motion from position 1 to position 2: Wm12(g=−gs. If the displacement is along an incline: singθ=gsfor down the incline and sing=−xx=−sfor up the incline. 4. Work done by a linear spring for motion from position 1 to position 2: Wk22(1 / 2) ()s5. Work done by friction: WNfkμExample 1. A force F= 200 N is applied on the 20 Kg block that is attached
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This note was uploaded on 04/06/2008 for the course PHYS 2305 taught by Professor Tschang during the Fall '08 term at Virginia Tech.