Summary
Vibrations and oscillations are described by: period, T (time required for one cycle); frequency, f (oscillations per unit time); f=1/T ; amplitude (maximum distance from the equilibrium)
- examples: mass hanging on a spring and pendulum
all systems have a distinctive natural frequency
when a system is excited at a natural frequency --> resonance
waves are vibrations moving through the medium
waves can be transverse or longitudinal one
waves are characterized by: speed v, frequency f ,and wavelength l; v=Fl
waves pass through each other, when overlap the total displacement is given by the superposition (sum) of the individual waves
when periodic wave is confined resonant patterns -- standing waves - can be produced
nodes (portions in the standing wave that do not move), antinodes (moves with the largest amplitude) ; fundamental standing wave and harmonics
two identical periodic wave sources with a constant phase difference produce an interference pattern which contains nodal and antinodal regions
waves do not go straight through openings or around barriers --> they suffer diffraction. The diffraction pattern depends on the relative sizes of the openings and the wavelength