Physics Sound Review
A sound wave has a wavelength of 20 m. Find its frequency.
340 (speed of sound in air) / 20 = 17 Hz
What type of waves are sound waves?
Longitudinal
If a sound wave's frequency is 100 Hz, what is its period?
P = .01
what medium do sound waves travel fastest in and why?
Solids because the particles are pacted tightly together rather than a gas where the particles are more spread out
Definition of Rarefaction
a disturbance in air in which pressure is lowered. Opposite of Compression.
Range that humans can hear sound
between 20 Hz and 20,000 Hz
Definition of Loudness
characteristic of a sound this a psychological correlate of amplitude
Two factors that DO NOT affect the speed of sound
frequency and amplitude
Definition of Pitch
how high or low sound frequencies appear to be
Two factors that affect the speed of sound
temperature and material (medium)
Definition of Compression
the act of squeezing material and reducing its volume. Opposite of Rarefaction.
Definition of The Doppler Effect
the change in frequency of a wave for an observer moving relative to its source. (Ambulance going by as you stand on the street watching it) Pitch does not change - only loudness changes.
Definition of Medium
the intervening substance through which impressions are conveyed
Definition of Sound
the movement of compression waves hitting our ears. The air molecules vibrate back and forth, but do not travel.
Velocity formula
velocity = wavelength x frequency
A wave's velocity is 90 m/s with a frequency of 6 Hz. What is it's wavelength?
wavelength = 1.5 meters
Wavelength formula
wavelength = velocity / frequency
Definition of Resonance
when two things vibrate at the same frequency