Transcript Sound Waves - Miss Hinze`s Class

What to do…
•NO JOURNAL ENTRY TODAY
•Turn in any late or missing work.
•On the ZipGrade sheet:
- Write your name
- Write the date
- Write your period number
•Have out only a pencil!
After the CFA #2
• Take out your manuals
• Open to page 51 so I can check the notes
from yesterday.
• Wait quietly until the entire class is ready
to move on!
Sound Waves
Chapter 22, Section 3
Open to page 55 in your manuals.
Standards:
11.5: Compare and contrast the different parts of a wave.
11.6: Differentiate between transverse and longitudinal
waves in terms of how they are produced and
transmitted
Think about it. .
• In the space provided. How
would you define or describe
the difference between noise
and music.
Sound
• Is energy that travels in the form of waves.
• Are caused by vibrations
• Are longitudinal waves
• Decibels (dB) are used to measure the intensity
or loudness of sound.
Frequency and Pitch
• Pitch is the highness or lowness of a sound
– The pitch depends on the frequency of the sound
waves
• The higher the frequency, the higher the pitch
• The lower the frequency, the lower the pitch
Frequency
• Most people can’t hear sound frequencies above
20,000 Hz, which are ultrasonic waves.
• Sub sonic waves have frequencies below 200 Hz.
Intensity and Loudness
• Intensity of a sound wave depends on the
amount of energy in each wave.
• Loudness is the human perception of sound
intensity.
– The higher the intensity and amplitude, the louder
the sound.
The Decibel Scale
The Doppler Effect
• The change in wave frequency due to a
moving wave source is called the Doppler
Effect.
– The Doppler Effect is observed when the
source of sound is moving relative to the
observer.
The Doppler Effect
Noise Pollution
• Noise pollution includes sounds that are
loud, annoying, or harmful to the ear.
• Sources include
–
–
–
–
–
jackhammer
jet engine
highly amplified music
highway or traffic
talkative students during a test (or other quiet
time)
Music
• Music is created using specific pitches
and sound quality and by following a
regular pattern.
– The most common kind of sound is noise,
which has no set pattern and no definite
pitch.
Resonance
• If the sound that reaches an object is at the
same frequency as the natural frequency of
the object, the object will begin to vibrate at
this frequency.
• Good singers can shatter a wine glass with
their voice using resonance.
Musical Sounds
• Sound quality describes the differences
among sounds of the same pitch and
loudness.
• Interference is the ability of two or more
waves to combine and form a new wave.
Acoustics
• Acoustics is the study of sound.
• The effect produced by many reflections is
called reverberation.
– Soft porous materials and certain room shapes
can reduce excess reverberation.