Wave motion is the most universal physical phenomenon, we discover the wave motion all around us. Mechanical waves—acoustic wave, water wave Electromagnetic waves—radio, light wave Matter waves—electron wave
1. Why we introduce the concepts of work and energy? F ma CWE theorem r r total = CWE theorem Conservation of energy (More universal) 2. About the systems that we discuss Ignore the size, internal structure, internal motion, deformations, and thermal effects
Collisions: All around us (cars, buses) Grand astronomical scale (stars, galexies) Nuclear, atomic and molecular physics The impulse-momentum theorem relates the change in the momentum of a system to the total force on it and the time interval during which this total forces acts
All around us: wheels, skaters, ballet, gymnasts, helicopter, rotors, mobile engines, CD disks, … Atomic world: electrons— “spin”, “orbit”. Universe: planets spin and orbiting the sun, galaxies spin, …
