period, frequency, angular frequency (Section 10.6)
position, velocity, acceleration, and energy in simple harmonic motion
(Section 10.5)
resonance (Section 10.10)
graphical analysis of SHM (Section 10.7)
Mastering the Concepts
An isotropic source radiates sound uniformly in all directions. Assuming that no energy is absorbed by the medium and there are no obstacles to reflect or absorb sound, the
intensity I at a distance r from an isotropic source is
In a transverse wave, the motion of particles in the medium is perpendicular to the direction of propagation of the wave. In a longitudinal wave, the motion of particles in the medium is along the same line as the direction of propagation of the wave.
The speed of a mechanical wave depends on properties of the wave medium. More restoring force makes faster waves; more inertia makes slower waves.
A periodic wave repeats the same pattern over and over. Harmonic waves are a special kind of periodic wave characterized by a sinusoidal function (either a sine or cosine function).
If a periodic wave has period T and travels at speed u, the repetition distance of the wave is the wavelength:
The principle of superposition: When two or more waves overlap, the net disturbance
at any point is the sum of the individual disturbances due to each wave.
Reflection occurs at a boundary between different wave media. Some energy may be transmitted into the new medium and the rest is reflected. The wave transmitted past the boundary is refracted (propagates in a different direction).
Coherent waves have the same frequency and maintain a fixed phase relationship with one another. Coherent waves that are in phase with one another interfere constructively; those that are 180° out of phase interfere destructively.
Diffraction occurs when a wave bends around an obstacle in its path.
In a standing wave on a string, every point moves in SHM with the same frequency. Nodes are points of zero amplitude; antinodes are points of maximum amplitude. The distance between two adjacent nodes is <a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=jpg::::/sites/dl/free/0073512141/663819/ch11_6.JPG','popWin', 'width=NaN,height=NaN,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (0.0K)</a>
