Key Equations

Key Equations

Work done by a force over an infinitesimal displacementdW=F→·dr→=|F→||dr→|cosθdW=F→·dr→=|F→||dr→|cosθ
Work done by a force acting along a path from A to BWAB=∫pathABF→·dr→WAB=∫pathABF→·dr→
Work done by a constant force of kinetic frictionWfr=−fk|lAB|Wfr=−fk|lAB|
Work done going from A to B by Earth’s gravity, near its surfaceWgrav,AB=−mg(yB−yA)Wgrav,AB=−mg(yB−yA)
Work done going from A to B by one-dimensional spring forceWspring,AB=−(12k)(xB2−xA2)Wspring,AB=−(12k)(xB2−xA2)
Kinetic energy of a non-relativistic particleK=12mv2=p22mK=12mv2=p22m
Work-energy theoremWnet=KB−KAWnet=KB−KA
Power as rate of doing workP=dWdtP=dWdt
Power as the dot product of force and velocityP=F→·v→P=F→·v→