Ch5_OringerR


 * Ross Oringer Chapter 5 Wikilog**

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Chapter 5- Section 1
In this image, I see a person strumming a string, and it produces a loud noise. You can tell it is loud because another person's reaction shows him screeching, and his hair blown away by this loud pitch. Also, there is a dog silently strumming a one string guitar.
 * What Do You See?**

Guitarists are able to make different sounds buy the positioning of their fingers on the instrument. Also, by how much force apply when strumming the guitar's strings. The tighter, the higher the pitch. Shortening the string creates a higher pitch also. To make a high sound, the person would keep the hand that is not strumming not a far distance away because shortening the distance of the string makes a higher pitch.
 * What Do You Think?**

5/9/11 http://www.careersinmusic.com/sound-technician.aspx Road technicians, or road crew, are responsible for creating nice sounds at concerts for bands. Before the show, they place the instruments where they know will make the best sounds. During the show, they work on the sound boards, controlling microphones and amplifiers. Sound quality is important. Everything needs to sound right, and no squeaky noises from extremely high pitched noises are good for an audience. They band needs to be heard. Singers need to be heard over the instruments, and during instrument solos, they get the most volume.
 * Road Technician Career**

5/9/11 **Summary**: To produce sound, something must vibrate. Two variables of vibration are length and tension. Different sounds are created by placing your fingers on different parts of the guitar neck. Shortening the string created a higher pitch. When adding mass to the mass hanger, the pitch changed, because the string tightened, creating more tension. as tension increased, sound pitch increased. When tuning an instrument, the player can either tighten or loosen the strings to make different sounds. Increasing the tension and decreasing the length increase pitch. In drums, the head of the drum vibrates. The length or area of the vibrating surface will behave in the same way as the string.
 * Physics Talk**

1. As the tension of the string increases, the pitch also increases. 2. When decreasing the length of the string, the pitch increases. 3. When adding mass to the mass hanger, the tension of the string increased, which will always increase the pitch. 4. A sound is created on a percussion instrument when it is struck on the head, creating a vibration.
 * Checking Up Questions **

5/9/11 http://tribalvillages.org/deaf-essays/Evelyn-Glennie.html Dame Glennie is a deaf percussionist that is very special. Hearing is a specialized form of touch. You can hear and feel vibrations. Someone who is deaf can hear/feel sounds. As the frequency gets higher and ears become more efficient, they drown out the more subtle sense of feeling the vibrations. She was able to distinguish the rough pitch of notes by associating where on my body she felt the sound. The low sounds were felt in her legs and feet and high sounds felt in the face, neck and chest. Dame can see items move/vibrate. An electrical signal is generated in the ear and various bits of other information from our other senses all get sent to the brain which then processes the data to create a sound picture. The various processes involved in hearing a sound are very complex but we all do it subconsciously so we group all these processes together and call it simply listening. Dam Glennie is able to become a famous percussionist who is deaf, and the ability to use her stronger senses of touch and sight are helping in the matter.
 * Inquiring Further**

5/10/11 ƒ=sqrt(T/4m*L) ƒ is frequency, T is tension, m is mass of string, L is length of string ƒ is proportional the square root of tension: doubling frequency requires 4 times the tension; square root relationship ƒ is proportional to 1/sqrt(L): doubling frequency, you need 1/4 the length; inverse square root relationship If the mass of the string increases, the frequency is lower. Inverse square root relationship In a piano, they move slower. To double frequency and multiply the length by four, that isn't practical for the piano. You can change the note without having such a long length. A different material creates a different "m".
 * Physics Plus**

5/10/11 1a. You can change the tension by adding mass to the string. When adding mass, more tension is created. 1b. Changing the tension changes the sound. The greater the tension, the higher the pitch. The lower the tension the lower the pitch. 2a. You can change the length of a string on a guitar or a violin but applying force to different frets on the guitar's neck. High pitches are created when pressing closer to the head. 2b. When you decrease the length, the pitch increases. It is an inverse square root relationship. Quadruple the length, you half the pitch. 3a. You can increase the length. When adjusting the tuners on the neck of the guitar, you change the tension of the string and keep the pitch the same. 3b. You can change the tension or the thickness of the string and keep the pitch the same by moving your fingers on the frets. 4. If you decrease the length and increase tension of the string at the same time the pitch would be very high. If you decreased the tension and increased the length the pitch would be very low. 5a. A guitarist plays different notes on a guitar and violin. The instruments are tuned by changing the position of their fingers on the strings, making the strings longer or shorter for different pitches. The amount of strings can differentiate the pitches. 5b. Instrument tuners can increase or decrease tension on the strings. The more tight they are adjusted, the greater the pitch. 6a. The tuners on the guitar change the tension of the strings, making a variety of pitches. 6b. Guitars need tuners because some times, you need high pitches and other times you need low pitches. If there was no offer, than the guitar wouldn't be effective in many songs. 6c. As the strings stretch, the tension is decreased, making a lower pitch. 7a. The frets make the strings longer or shorter. Different pitches are created depending on where the fingers are placed. 7b. Violins and Cellos do not have frets. 7c. These instruments are more difficult to play because you need to be accurate with the placing of the fingers. There are no frets telling you were to place your fingers. 8. For a guitar in a light show, I would want it to make high pitched noises, because concerts are loud. By making high pitched noises, I would design the guitar to have strings with a lot of tension. Also, I would make sure that the strings are short in length.
 * PTG**

Musicians make different pitches when playing the guitar based upon two variables: the tension of the strings and the length of the strings. In order to create different pitches, these variables need to be altered. To create higher pitches, guitarists need to decrease the length of the strings. Also, to create higher pitches, they need to increase the tension of the strings. Tension can be added by adding mass. They would also press their fingers on different parts of the neck, making the string longer or shorter. For a lower pitch, they would press their finger closer to the top. If someone was playing air guitar they would position their finger lower on the neck to make the higher pitch. Air guitarists place their fingers low because they are playing a solo, and need to be heard as the only instrument. The high pitch will make the instrument loud.
 * What Do You Think Now?**

Chapter 5- Section 2
This girl is surfing on top of a large slinky. The slinky is being acted on by outside forces, and this force happens to give it wave like motions. This allows the girl to surf on the slinky.
 * What Do You See?**

The particles in a wave make an up and down motion. When traveling, they reach a high point, and that is the upward motion. When reaching the highest point, they began to fall, slowly falling to the surface. This wave like motion is similar to a parabola shape. Waves are made in the ocean because of the moon's gravitational pull. This pull creates tides in the oceans all over the world. The waves that are bigger are because they are closer to the gravitational pull.
 * What Do You Think?**

5/11/11 **Summary**: //frequency//- (f) how often a wave passes a point in one second #wave/second-Hz //period//- (T) how many seconds it takes for one wave to pass #seconds/wave-Seconds *frequency and period are reciprocals //wave length//- distance from one point on a wave to the same point on the next wave (lambda) //wave speed//- speed it takes for a wave to travel from one place to another; measured as total distance over total time: lambda times frequency //amplitude//- y-axis; represents the amount of energy of a wave (distance) //traveling wave//- regular and repeating pulses //pulse//- single disturbance in the medium //crest//- position of maximum amplitude (+A) //trough//- position of minimum amplitude (-A) //transverse wave//- move side to side; energy travels perpendicular to the motion of the particle //longitudinal wave//- pulses; compressions moving down; energy travels parallel to the particle motion //medium//- substance that carries the wave //node//- a point on a standing wave where the medium is motionless //antinode//- a point on a standing wave where the displacement is the largest //wave//- transfer of energy without a transfer of mass
 * Physics Talk **

Superposition Principle: when waves hit at the same crest, you add the heights When it is a crest and a trough, you subtract



1. A wave is a transfer of energy with no net transfer of mass. 2. A transverse wave moves side to side and the energy travels perpendicular to the motion of the particle. A longitudinal wave energy travels parallel to the particle motion. 3. A node is a point on a standing wave where the medium is motionless. In an antinode, it is a point on standing wave where the displacement is the largest.
 * Checking Up Questions **

5/12/11 1a. Amplitude is how far you go side to side (meters). For wavelength, you measure the crest and multiply by two because of the trough (meters). Frequency measure how many times your hands go back and forth. Every time it goes up and back, that is 1 cycle, and you do how many times per second. For speed, the total distance over the total time (m/s). 1b. Amplitude is in meters.Wave length is in meters. Frequency is 1/seconds. Speed is meters per second. 1c. Amplitude is unrelated to anything. Frequency and wavelength are inversely related. Wave speed depends on the medium. 2a. If frequency increases, wave length decreases. By changing wave speed, you change tension in string. 2b. Frequency and wave length change. 2c. Wave speed doesn't change. 3. The wavelength can be measured from one point on one wave to the same point on the next wave. 4. Frequency is the number of waves over a time of a second. You can see how many waves are passing and divide it by how long the video you recorded. 5a. Wavelength units are meters. 5b. Frequency units are measured in Hertz (Hz) which is the number of waves over time. 5c. Speed is measured in meters/second. 5d. The speed can be measured by wavelength times frequency. 5e. wavelength (meters)*frequency (1/seconds)=meters/seconds (SPEED) 6a. Its a wave pattern that stays in one constant position. 6b. 6c. Wavelength could be measured by finding the distance from one completed crest to trough. 7a. Transverse waves, energy travels perpendicular to the motion of the particle. In longitudinal waves, energy travels parallel to the motion of the particle. 7b. Transverse waves move from back to forth. Longitudinal waves move in an up and down motion, or compressions moving down. 8a. To make wavelength shorter, increase the frequency by shaking the slinky faster. 8b. When shaking it slower, the frequency decreases, and the wavelengths increase. 9a. (n)(1/2)(wavelength) = L 5*.5*wavelength = 5 = 2 m 4* .5* wavelength = 5 = 2.5 m 3 x .5 x wavelength = 5 = 3.33 m 2* .5* wavelength = 5 = 5 m 1* .5* wavelength = 5 = 1 m 9b. The greater the frequency, the shorter the wavelength 10a. (n)(1/2)(wavelength) = L 1*.5* wavelength = 10 = 20 m 10b. The frequency is ½ Hz. 10c. wave speed = f*lambda =.5*20 = 10 m/s 11a. The two waves would add together to make an amplitude of 5 cm. 11b. If they were on opposite sides of the coiled spring, the amplitude would be 1 cm. You get this by subtracting. 12. speed=distance/time =9/2.64 =3.41m/s 13a. The clothes=nods. Space between=antinodes.
 * PTG**

13b. (n)(1/2)(wavelength) = L 3*1.5*wavelength = 9 = 6 m 13c. The wavelengths could be 3, 1 and a half, etc when being cut in half.

Water in the ocean moves to make waves that are both small or powerful. This wave formed is a transverse wave. The water forming the wave has particles that move up and down about the medium. The medium is wind. The wind moves left and right, back and forth. This happens constantly. The water's frequency is high. there are plenty of waves that are created before crashing, reaching the shore.
 * What Do You Think Now?**

Chapter 5- Section 3
The man is playing an instrument that looks homemade. It has one string and is made off of a broom stick. The trained lady is playing a stand up bass with many strings. The man's instrument probably doesn't make many pleasant sounds.
 * What Do You See? **

When changing the tension, you are either taking away or adding mass. When adding tension, the pitch becomes higher. When taking away tension, the pitch becomes lower. It changes because tension is a part of vibration.
 * What Do You Think? **

5/14/11 **Summary**: The length of the string is always half the wavelength of the lowest-frequency standing wave. When pitch increases, frequency increases. The equation for wave speed is frequency times wavelength. When length of a string decreases, wavelength also decreases for a standing wave. An inverse relationship is a relationship where decreasing one variable increases the other variable. For example, when decreasing the wavelength, frequency and pitch increase. As frequency increases, the speed of the wave increases. A larger tension force makes a bigger acceleration on that part, creating a fast vibration. In a direct relationship, increasing one variable increases the other variable, and the same for if it decreases. For example, increasing the wave speed increases the frequency and pitch. L = [(n)(lambda)] / 2.
 * Physics Talk**

1. When decreasing the wavelength, frequency and pitch increase. F = v / lambda. If the wavelength gets shorter, the denominator on the right side of the equation gets smaller. the fraction increases, then the left side of the equation gets larger, so the f increases, creating an inverse relationship. 2. The greater the tension, the higher the pitch. If tension decreases, pitch decreases. 3. The weaker the tension, the slower the wave speed. 4. L = [(n)(lambda)] / 2
 * Checking Up Questions **

5/18/11 As the tension increases, the pitch increases. This increases the frequency. The speed of the wave gets bigger, and there are more waves that can be carried through, increasing the wave per second. The particles are more tightly joined so as one moves, there isn't as much elasticity between them. When tension increases, the pitch increases. When tension decreases, pitch decreases. The relationship is a direct square root. Adding mass creates more tension. The amplitude decreased as the tension increased.
 * What Do You Think Now?**

Chapter 5- Section 4
The people in this image are playing instruments. These instruments are homemade from household products like water pipes and bottles. They are having difficulty making nice sounds from these instruments.
 * What Do You See?**

Flutes and organ pipes make high pitched sounds. The sounds are made from holes. When blowing into the instrument, based upon the whole that is pressed, a different sound will be made.
 * What Do You Think?**

5/19/11 **Summary**: Sound is like a string, and it is a compressional wave. The medium of sound traveling is the air. At the bottom of a test tube there is no vibration and the amplitude is zero so there is no sound. It is at the node of a wave. The node is the closed point of the wave. It is the very minimum of the ampllitude. On the other hand, at the open end, it is the loudest it can go and the amplitude is at its maximum. This is the antinode of a wave. Sound waves travel by moving around barriers. Diffraction is this ability for the waves to be able to bend, spread out and change direction in order to get into an opening. The smaller the opening the more diffraction. The bigger the opening, the less diffraction. Diffraction is basically the bending of a wave. The size of the opening determines the wavelength and volume. If both ends of a tube are open, it forms a vibrating column of air. The displacement of the air molecules are zero. When one end is closed, the pitch and frequency decrease. If the both ends are open it is 1/2 lambda. The Wavelength is double then if it were closed.
 * Physics Talk**

1. The medium of the sound traveling is air. While traveling through the air the sound diffracts. From wave to wave, it can enter and go through different barriers or through different boundaries. 2. Waves can diffract by bending. They find openings. They change direction (and magnitude) in order to get through different sized barriers or doorways. 3. The speed can be determined by multiplying the wavelength and the frequency. If the wave speed is constant than the frequency and wavelength are also constant.
 * Checking Up Questions **

5/20/11 1a. Similarities: the sounds are produced by standing waves and they're an octave apart. 1b. Shortening the string or tube makes the frequency higher. In a string, there are nodes at both ends. In a closed tube, there is a node at one and an anti node at the other. 3a. 11 meters 3b. 3c. The wavelength is 44 meters. It is a closed tube which includes the 1/4. 3d. The two are indirectly related. Speed must remain constant. As wavelength increases, frequency decreases and visa versa. 4a. 12 meters (3*4) (closed tube) 4b. ƒ=v/wavelength 340/12 =28.3Hz 4c. 6 meters (open tube) 4d.ƒ=v/wavelength 340/6 =56.6 Hz  5. A shorter pipe has a much higher frequency. This is three times greater. 6a. Diffraction defines this question. 6b. 7. v=d/t 340=1600/t t=4.71 seconds
 * PTG**

5/20/11 Flutes and organs produce sound that are heard in the air through their tubes. One end of the tube is open, and the other has a mouth piece that puts air through the instrument. Because of this open end, there are antinodes which are formed at the end. Anti nodes are the loudest part of a wave because they have the maximum amplitude. As seen above (3b of the PTG), this is an image of a tube with an open end. You can tell the sound will be loud because it has a large area. The longer the tube is (length), the lower the frequency. at the end which produces a loud sound. If wave speed is increases, the frequency has to increase. They share a direct relationship. The wave speed will always be constant (Vair equals about 340 m/s) because temperature is a factor of finding wave speed.
 * What Do You Think Now?**