sound

sound is produced by…

a vibrating source and is a mechanical wave that propagates through a medium from one location to another. Sound is created when a surface vibrates and disturb the air that surrounds it, producing a series of compression and rarefactions that travel away from the surface as a longitudinal wave

speed of sound is different in air, liquids and solids because

their particles are spaced apart differently, and soli particles are arranged closer to one another, so vibration of particles can be transferred throughout the solid faster, and sound travels faster

why must sound waves need a medium

1. Because sound waves require the oscillation / vibration of particles in a medium to be transferred

what is the procedure of determining the speed of sound in air and calculations

loudness of sound is determined by…

amplitude

pitch of sound is determined by

frequency

echo is produced by

the reflection of sound

sound waves bounce off a surface and reflect back to the ears

ultrasound is

sound with a frequency higher than 20kHz

sound travels at…

the same speed as audible sound in the air

what is ultrasound used for

deep cleaning, quality checks and pre-natal screening

if pitch of sound increases, what things change?

amplitude remains the same, frequency increases, period decreases, wavelength remains the same, wave speed increases

frequency of sound depend on

sound source and is independent of the medium

when temperature increases,

wave speed increases so wavelength increases

while frequency doesn’t change

range of frequencies we can hear

20Hz to 20kHz

music note vs noise

regular vibrations vs irregular

notes of different qualities have

different waveforms