Transcript Sound - Educator Pages

Daily Science (pg. 52)
1.
2.
3.
Name an example of a transverse wave and a
longitudinal wave.
Put these numbers into scientific notation:
1. 0.0000000347
2. 40500000000
3. 0.0000012
4. 109000000000000000000
Divide the following numbers
1. 3.0 x 108 / 6.7 x 10-12
2. 9.54 x 1037/ 1.07 x 1013
3. 6.7 x 10-14 / 8.1 x 10-6
Sound
Pg. 53
Properties of sound
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Sound waves- longitudinal waves that are caused by
vibrations and travels through a medium
Speed of sound-depends on the material and the
temperature through which it travels
Loudness-determined by intensity
Intensity-the rate at which a sound wave transmits
energy (depends on amplitude and distance from source).
Intensity
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Measured in decibels (dB)
Threshold of hearing: quietest sound a human can
hear (0 dB)
Threshold of pain: sounds louder can cause
deafness (120 dB).
Ex. 30 dB- cat purring
50 dB- normal conversation
90 dB- lawn mower
150 dB- nearby jet airplane
Sound characteristics
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Pitch-measure of how high or low something sounds
Higher frequency  higher pitch
Any sound that has a frequency below human
hearing is called infrasound.
Any sound with a frequency above human hearing is
called ultrasound.
Musical instruments
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Rely on standing waves
The player controls the vibrations of the standing
waves
Instruments use resonance to amplify sound.
Resonance-a phenomenon that occurs when two
objects vibrate at the same frequency.
The Ear
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The ear senses vibrations, amplifies
them, and transmits them to the brain.
There are 3 regions: outer ear, middle
ear, inner ear.
Ultrasound and Sonar
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Reflected waves are used to determine distances
and to create images.
Reflected waves from an ultrasound are put into a
computer image called a sonogram.
Sonar uses reflected waves to determine distance
under water (calculates using the velocity equation).
Bats use ultrasound to fly and locate food.
Pg. 54
1.
Use page 549 in the book to help you label the
parts of an ear. Describe IN YOUR OWN WORDS
how sound travels through the ear.
2.
Read the article on the corner of my desk. On
pg. 54 summarize the article using 5 vocabulary
words we have talked about. Include a
paragraph on whether or not you think the
experiment the scientists was ethical. Provide
an example of something they could have done
differently.