Waves (Etkina 20) Flashcards
the object that causes the vibration
source
short disturbance in surrounding medium
pulse
the moving circular disturbance created by the source on water
wave front
every point on the wave front has the same … at the same time
displacement from equilibrium
longitudinal wave: the vibrational motion of the particles/layers of the medium is … to the direction of propagation of the disturbance
parallel
transverse wave: the vibrational motion of the particles/layers of the medium is … to the direction of propagation of the disturbance
perpendicular
when a wave encounters any boundary between different media, some of the wave is
reflected back
sound is created by vibrations that cause … which travel through air from one place another
air pressure changes
sound waves are
longitudinal
period: … for one complete vibration of a … in the medium anywhere along the path
time period; point
frequency: the number of … per second of a … in the medium as the wave passes
vibrations; point
amplitude: the … of a … of the medium from its equilibrium position as the wave passes
maximum distance; point
speed: the distance a … travels during a …, divided by that time interval
disturbance; time interval
disturbance pattern of a wave repeats at a distance Tv, which separates neighboring locations on the wave that have the same displacement y and the same slope …
wavelength
y (x,t) =
y(x,t) = Acos[2T(t/T-x/ lambda)]
`2 points are in phase if at every clock reading their .. are exactly the same
displacements
2 points separated by a distance equal to an integer multiple of … are always in phase
wavelengths
the period and frequency of a wave depends on the
vibration source
wave speed depends on the … and the …
medium; type of wave (pulse)
… waves travel more slowly than … waves due to the types of … of the medium that occur when the waves propagate
transverse; longitudinal; deformation
the energy per unit circumference length and per unit time crossing a line perpendicular to the direction that the wave travels decreases as …, where r is the distance from the … of the wave
1/4; point source
the energy per unit area per unit time passing across the perpendicular to the direction that the wave travels decreases as …, where r is the distance from the point source of the wave
1/r^2
intensity of a wave is the energy per unit area per time interval that crosses perpendicular to an area in the medium through which it travels. I =
delta U/ delta t * A = P/A
reflected pulses are
inverted