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WAVE and SOUND. Sound Terminology. Amplitude - is the maximum distance the particles in a wave vibrate from their rest positions. Frequency - the number of waves produced in a given time. Sound Terminology.
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Sound Terminology Amplitude- is the maximumdistance the particles in a wave vibrate from their rest positions. Frequency - the number of waves produced in a given time
Sound Terminology • Wave Velocity - is the speed with which a wave crest passes by a particular point in space • It is measured in meters/second. • Wave Velocity = Frequency Wavelength
Speed of Sound • Medium velocity m/sec air (20 C) 343 air (0 C) 331 water (25 C) 1493 sea water 1533 diamond 12000 iron 5130 copper 3560 glass 5640
Pitch -description of how high or low the sound seems to a person Higher Pitch means Increased Wave Frequency Tone: A sound of distinct pitch, quality, and duration; a note. Sound Terminology . Loudness- how loud or soft a sound is perceived to be. CLICK HERE: Loudest Speakers
Analysis Question: What is the relationship between PITCHAND WAVELENTH?
Sound Terminology • Acoustics: the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound. • Decibel: ( dB) is used to measure sound level, but it is also widely used in electronics, signals and communication.
Are Sound vibrations visible??? • http://www.kirotv.com/videos/news/video-what-does-washingtons-loudest-car-stereo/vCM4g4/
Think, Pair and Share Complete the following Hypothesis: If you are exposed to sounds louder than 200 decibels, then your internal organs most likely will _____________________________________________ because __________________________________________________.
Sounds and Mediums Waves must have medium in order for sound to be heard Of the three mediums (gas, liquid, and solid) sound waves travel the slowest through gases, faster through liquids, and fastest through solids. Temperature affects the speed of sound. http://www.ndt-ed.org/EducationResources/HighSchool/Sound/tempandspeed.htm
Ultrasound - sound waves with frequencies abovethe normal human range of hearing Sounds in the range from 20-100kHz Infrasound - sounds with frequencies below the normal human range of hearing. Sounds in the 20-200 Hzrange
Obstetric Ultrasound • Date the pregnancy (gestational age) • Confirm fetal viability (if it is living) • Determine placement of fetus, intrauterine vs ectopic • Check the location of placenta in relation to the cervix • Check for the number of fetuses (multiple pregnancy) • Check for major physical abnormalities • Assess fetal growth • Check for fetal movement and heartbeat. • Determine the sex of the baby
Other Uses of Ultrasound • Medical • Detecting blood-clots in arteries and veins • Eye scans • Any soft tissue scans (organs, skin, muscles, etc) • Biopsies • Break up kidney stones • Chemotherapy - delivery of medicines using high frequency • Jewelry Cleaning - UltraSonic • Humidifiers • Identification Badges • Sonar - in submarines and ships • Product testing – finds flaws in materials • Used in Horses to detect injuries • Used in Beef Industry to evaluate fat thickness, rib-eye area and to improve breeding procedures
Ultrasound in Animals • Echolocation (Echoes) - Sonar • Using echoes for communication, navigation and foraging • Bats and Whales / Dolphin, Shrews, Cave-dwelling birds, Tenrecs • Humans use of echolocation • Called “Perceptual Mobility” • Blind persons
Whales, elephants, hippopotamuses, rhinoceros, giraffes, Okapi and alligators are known to use infrasound to communicate over distances—up to hundreds of miles in the case of whales. • Tigers use low frequency growls to paralyze their prey • It has also been suggested that migrating birds use naturally generated infrasound, from sources such as turbulent airflow over mountain ranges, as a navigational aid.
ANSWER THE FOLLOWING: TRUE OR FALSE: SIGHT IS THE PRIMARY SENSE FOR ALL ANIMALS COMPLETE THE FOLLOWING STATEMENT: SOME ANIMALS NEED INFRASOUNDAND ULTRASOUNDBECAUSE __________________________________________________________________________________________________ HUMANS NORMALLY DON’T NEED INFRASOUNDOR ULTRASOUNDBECAUSE ____________________________ EXPLAIN THE EVOLUTIONARY ADAVANTAGES OF INFRASOUND AND ULTRASOUND.
Infrasound: Paranormal Activity and Religious Activity • Documentation of infrasound and ghost activity • Ghosts and spirits emit low Frequency sound waves • Extreme bass of Organ music triggers spiritual feelings or a feeling of a person nearby or a presence.
Infrasound and Other Mental and Physical Effects • Infrasound can cause fear, have a negative effect on a person physically and even cause death. • Elevated blood pressure and heart rate, nausea • Release Endorphins leads to adrenaline response • Anxiety, coldness, tingling sensations, sorrow, shivers down the spine
WARM UP 3/12 WEDNESDAY Describe a situation where CONSTRUCTIVE INTERFERENCE would be necessary or beneficial. Describe a situation where DESTRUCTIVE INTERFERENCE would be necessary or beneficial.
Interference • The result of two or more sound • Waves Overlapping
Interference Constructive Examples Destructive Examples Noise Cancelling Headphones Pilots – decreases noise from high decibel environments Construction Workers • Iridescence • Bubbles • Butterfly wing colors • Musical Instruments • Instruments harmonize and become one sound
PITCH AND THE DOPPLER EFFECT • You are standing by the side of the road. A car horn blares as it comes toward you and passes you at constant speed. The PITCH of the horn that you hear • gets higher and higher as the source approaches and gets lower and lower as the source recedes • b. stays at a constant high pitch as the source approaches and then drops to a constant lower pitch as the source recedes • c. stays at the same constant pitch throughout the motion • d. maintains the same pitch except at the moment the source passes • e. varies too much to tell what the pitch is doing • DRAW A DIAGRAM TO EXPLAIN YOUR ANSWER
Doppler Effect Change in the frequency of a sound caused by the motion of either the listener or the source of the sound.
Sonic Booms • If the source is moving as fast or faster than the Speed of sound the sound waves pile up into a shock wave called a sonic boom. • Enormous energy • A sonic boom sounds very much like the pressure wave from an explosion • The crack of a bull-whip is a small sonic boom.
Sonic booms are usually associated with Space Shuttle Landings or large aircraft.
Resonance the frequency of sound waves exactly matchesthe natural frequency of an object. A Forced Vibration. An example of resonance: A motor that causes vibration in a piece of furniture in another part of the same house. These vibrations occur because the furniture has a natural frequency equal to the frequency of the vibrations set up by the motor. Mythbusters Resonance Bridge Video Clips
Mechanical Resonance can produce vibrations strong enough to destroy the object in which they occur. • For example, soldiers marching over a bridge can cause extreme vibrations at the bridge's natural frequency and shake it apart. For this reason, soldiers break step to cross a bridge. • In 1940 wind gusts at Puget Sound Narrows, Tacoma, Washington, caused a suspension bridge to vibrate at its natural frequency and the bridge collapsed.
In Music, resonance is used to increase the intensity (loudness) of a sound. The comparatively weak vibrations produced at the end of an organ pipe, for example, cause a column of air in the pipe to vibrate in resonance, thus greatly increasing the loud-ness of the sound. In humans, the vibrations of the vocal cords are reinforced by resonant vibrations in the oral and nasal passages. Video of Vocal Chords Steven Tyler Vocal Chords
Can the human voice shatter glass???? Mythbusters Rock Star Singing Kid Breaking Glass • Everything has a Resonant Frequency • the speed at which it will vibrate if bumped or otherwise disturbed by some stimulus, such as a sound wave • Glass wine goblets are especially resonant because of their hollow tubular shape • If a person sings the same tone as that ringing note, the sound of the voice will vibrate the air molecules around the glass at its resonant frequency, causing the glass to start vibrating as well. • If sung loudly enough, the glass will vibrate itself to smithereens.
Resonance and the Singing Glass Resonance The motion of your hand sets up a wave of vibration traveling through the glass. The vibrations cause air molecules to vibrate at the same frequency. The vibrating air molecules are the sound wave that you hear • Adding energy into the substance at its resonant frequency will force it to vibrate or resonate • As your finger slides and sticks along the surface of the rim, energy is added to the glass molecules and causes them to resonate. Glass Singing
Electrical Resonance Electrical resonance • is used to tune radios and television sets. • Tuning consists of establishing a circuit with a resonant frequency equal to the assigned frequency of the desired station.
Magnetic Resonance ImagingMRI • Medical imaging using powerful magnets, radio frequency and atoms in the body • Used for more detailed images of the heart, brain, etc. Used to detect cancers • No Ionizing radiation (cancer causing)
Colors of Noise • Different audio signals • used in engineering, electronics and physics • Each sounds different to the human ear • Each has a different spectral reading • White • Pink • Red (Brown) • Gray • Blue • Violet • Black • Green
White Noise • White noise does not vibrate at one specific frequency • It covers a range of frequencies. • Often used as sirens by the emergency services • It cuts through background noise and does not echo so it is easier to perceive the direction the vehicle is travelling.
White Noise Sound Machines Link: White Noise Sound Machines Used to help Babies sleep may be doing harm
HEARING LOSS TYPES • CONDUCTIVE • Sound doesn’t move correctly through the ear drum, ear canal or ossicles • Sounds like ears are plugged • Person may speak softly b/c their voice seems loud to them • Causes • Earwax • Punctured eardrum • Fluid in the ear • Genetic defect • Infection • Treatment • Surgery • Medicine • Hearing Aid • Cochlear Implant • SENSORINEURAL • Damage to the Cochlea or Nerves • 90% of people with hearing loss • Gets worse over time • Some can hear, but can’t understand what people are saying • Causes • Aging • Infections • Head Trauma • Genetics • Exposure to loud noises • Fluid build-up -Treatment: Usually can’t be treated • Depends on the Specific Damage • Hearing Aid • Cochlear Implant
Otoscope: Instrument used to view the ear drum Never use Q-tips!! Perforated Eardrum
Ear Tubes Decrease Pressure in the Ear Drainage is normal after surgery