Chap 10 Flashcards
Sound is:
a form of energy caused by vibration
Characteristics of sound waves
- requires a medium to propagate
-propagate at diff speeds in diff medium - can be reflected and absorbed
Sound can propagate through ______, ____ and ____ but not through ____
can propagate through:
- liquid, solid and gas
Cannot propagate through:
- vacuum
how does waves work
- when a surface of the object vibrate, air molecules near the surface will also vibrate and collide w the air molecules nearby
- this vibration is transferred from one molecule to another molecule beside it in the form of waves
sound is transferred _________ in solids
very rapidly
sound is transferred __________ in liquids
less rapidly
sound is transferred _________ in liquids
very slowly
Sound can be ____________ and _____________ when it hits the surface of an object
- reflected
- absorbed
the amount of sound reflected or absorbed depends on:
- depends on the surface of the object
What are good sound reflectors
hard and smooth surfaces
why can our ears differentiate the sounds that r heard
- bcuz of the different strengths n pitches in sounds
the strength or loudness of sound produced depends on :
the amplitude of the sound wave
pitch of sound depends on
the frequency of the sound produced
frequency is measured in the unit of
hertz (Hz)
reflection of sound waves produces
echo
Elaborate on echo
- produced when sound waves r reflected from a hard surface to the listener
- sounds the same as original sound but takes some time to reach the listener’s ears
-can be heard in enclosed places
Elaborate on Ultrasound
- a type of sound wave with a frequency of more than 20,000 Hz
- cannot be heard by humans but can be heard by animals such as bats that use it for navigation
the frequency of sound that can be detected by humans is within the range of
20 Hz to 20,000 Hz
