Chapter 16/17 - Waves
|Propagation of a Disturbance|
all mechanical waves require (1) some source of disturbance,
(2) a medium that can be disturbed, and (3) some physical
mechanism through which elements of the medium can influence
• energy is transferred over a distance, but matter is not.
• electromagnetic waves do not require a medium to propagate.
|A traveling wave or pulse that causes the elements of the disturbed medium to move parallel to the direction of propagation is called a longitudinal wave.|
|A traveling wave or pulse that causes the elements of the disturbed medium to move perpendicular to the direction of propagation is called a transverse wave.|
seismic waves are three-dimensional waves
that radiate out from a point underneath the surface of
the earth. Both longitudinal
(p-waves) and transverse
(s-waves) waves are generated.
|y(x,t) = f(x - vt)|
|y(x,t) = f(x + vt)|
|A derivation for you. . .|
Velocity on a String
Waves transport energy when they propagate thru a medium