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