Sound

1. Sound -

2. Sound is a form of energy that travels through matter as waves

3. Sound waves travel more slowly than light waves Speed of light waves is 300 million m/s Sound is 346 m/s

4. Sound does not travel in a vacuum like light! • Sound travels fastest through a solid because • the particles of a solid are close together • Sound travels slower through a liquid because the particles are spread out. • Sound travels the slowest through air because • the particles in a gas are so far apart or spread out (just the opposite of light).

5. Sound travels in waves like light! Crest – highest point of the wave Trough – lowest part of the wave

6. Sound waves are measured according to: Frequency the number of waves or vibrations in a specific unit of time (like a second) Wavelength measurement from the crest of one wave to another crest

7. Vibration Back and forth movements of matter

8. Waves are also measured by Amplitude the difference between compressions and rarefactions or the amount of energy in a wave

9. Compression is the part of the wave where particles are pushed together Greater air pressure Rarefaction is the part of the wave where there are fewer particles than normal. Lower air pressure

11. Quality of Sound

12. Pitch Measures highness or lowness of sound Relates to the frequency of the waves High frequency is a high pitched sound

13. Pitch Low frequency is a low pitched sound

14. Pitch & Amplitude High frequency = high sound (pitch) Low frequency = low sound (pitch) Small amplitude = quiet sound Large amplitude = loud sound

15. Frequencies are measured in a unit called a hertz (Hz)Different animals can hear different ranges of hertz Elephants can hear very low frequencies. They even communicate across many miles in a frequency so low, humans can not hear them! Bats and dolphins can hear very high frequencies!

16. SONAR SOundNavigation And Ranging When animals use sonar, it is called Echolocation or biosonar . Just like the sonar that is used by humans, the animals use a series of echoes to locate each other and find prey.

18. Loudness! Decibel– Unit used to measure the volume or intensity of sound Volumedescribes how loud or soft Intensityis a measure of the energy of a sound wave

19. Breathing 10 dB

20. Perfect decibel for a classroom????? 0!!!!!!!!!!! & to get fun Friday!

21. Resonance or Timbre Quality of a musical tone Who do you think has the best resonance?

22. Temperature makes a difference to sound! Hey, can’t you hear me? No man, it’s too cold where you are!

23. Sound moves faster at higher temperatures! Particles of matter move faster at higher temperatures because they take less time to collide and pass along the waves of energy.

24. My what big ears you have! Semicircular canal Cochlea & Auditory Nerve Anvil Hammer Ear Canal Eustachian tube Stirrup Ear Drum

25. The Ear Eardrum is connected to the hammer, anvil, and stirrup 3 tiny bones that transmit vibrations Auditory nerve – transmits information to brain Eustachian tube – connects middle ear to the throat keeps even air pressure in your ear Semi-circular canals – help you keep your balance

28. Man, that’s some vibration !!