Ch+5+_+PrezantJ

= **Section 1** =

What Do You Think
They make different sounds by applying pressure on different parts of the string. The shorter distance you cut the string off by, the higher the note will be. The would make the highest pitched notes on the thinnest string at the shortest distance on the string.

Physics Talk
-to produce sound, something must vibrate -vibrate: move back and forth rapidly -two variables changed the pitch of sound of our string during the investigate; the string's length and tension -variable: something that can change or vary during an investigation -pitch: how high or low a note is -When a string is shortened, it makes a higher pitched sound -When a string is made longer, it makes a lower pitched sound -adding the hanging masses to the string also changed the pitch because it added tension to the string. When the masses were heavier, the string made a higher pitched sound and vice versa -when it comes to percussion instruments, the instruments make sounds when they are hit and they vibrate

Checking Up
1. When the tension increases, the pitch of the sound that the string produces becomes higher. 2. When the length decreases, the pitch of the sound that the string produces becomes higher. 3. When you add mass to the mass hanger, the tension of the string increases, resulting in a higher pitched sound. 4. A sound is produced in a percussion instrument when the instrument is struck and it vibrates.

Inquiring Further #3
Dame Evelyn Glennie might be deaf, but that does not stop her from being an incredible percussionist. She explains that hearing is not the only way to understand a sound, you can also feel the sound's vibration, which is how she makes her music. Glennie makes a very true statement when she wrote, "deafness does not mean that you can't hear, only that there is something wrong with the ears." People who are totally deaf can still feel the vibration of sounds. She feels the vibration of low sounds in her lower body while she feels the vibration of high sounds in her upper body. Though she is deaf, she says she is only profoundly deaf. She can understand people by reading their lips as they talk. She can hear the phone ring by hearing it vibrate.

Vocabulary
crest - posotion of max. amplitude trough - position of min. amplitude (-A) amplitude - represents the amount of energy a wave has. (distance) frequency (f) - how often a wave passes a point in 1 second. #wave / 1sec = 1/s = Hz period (T) - how many seconds it takes for one wave to pass #sec / 1 wave = s T = 1/f frequency and period are reciprocals wave length - distance from a point on 1 wave to the same point on the next wave wave speed = total distance / total time wave speed equation : v =lambda / T = lambda * 1/T = lambda * f medium - the substance that carries the wave transverse wave : energy travels perpendicular to particle motion longitudinal wave : energy travels parallel to particle motion

Physics Plus
ƒ = sqrt (T / 4m*L) f = frequency T = tension m = mass of string L = length of string ƒ or sqrt T doubling frequency requires 4x Tension ƒ or 1 / sqrt(L) y = 1 / sqrt(x) doubling frequency requires 1/4 the length

What Do You Think Now
Guitarists make different pitched sounds by shortening the string or adding tension to the string. They shorten the string by pressing on frets closer to where they are plucking. They add tension to the strings by using the tuners and tightening them. On a guitar, you would make a higher pitched sound by pressing on frets closer to where they are plucking.

PTG
1a. You can change the tension by adding more or less weight to the string. 1b. When the string has more tension, it makes a higher pitched sound compared to when the string has less tension 2a. You can change the length by pressing on the string at different points. 2b. The shorter the string, the higher the pitch, and the longer the string, the lower the pitch. It is an inverse squared relationship. 3a. You can change the tension and keep the same pitch by taking away weight but making the string a shorter distance. 3b. You can change the length and keep the same pitch by adding weight when the string is longer and taking away weight when the string is shorter. 4.If the tension became tighter and the string was shorter, the pitch would be higher than normal. If the tension became less and the string was shorter, it would be about normal. If the tension became less and the string was longer, it would be lower than normal. 5a. They play higher notes by holding the frets that are closer to where they are plucking. They play lower notes by holding the frets that are farther to where they are plucking. 5b. They change the pitch by adding tension to the strings. 6a. They add or take away tension on the strings. 6b. The guitar needs tuners in order for the strings to not get too loose and only be able to play lower pitched notes. 6c. In heat, the strings become looser, meaning they lose tension, meaning they play lower notes. 7a. The frets are to show where to place your fingers if you want to play a lower or higher pitched note. The closer frets to where you are plucking make higher pitched notes and vice versa. 7b. Violins and cellos do not have frets. 7c. Yes, violinists require more accuracy because frets are not there to show where to put your fingers to play certain notes. 8. For the show, the instrument I would create would have 3 different strings, each of different tensions. The first string would be for highest notes and the last string would be for the lowest notes. The middle string would be for notes in-between. It would have different frets to show where to put your fingers if you want to play a higher or lower pitched note. Tuners would be at the end of the string in case the strings loosen up too much. In summary, this instrument would be very similar to a guitar except with 3 less strings.

=Section 2=

What Do You Think
Water moves when it is in the ocean by going up and down, resulting in a waving motion. In the open ocean, the water moves up and down, but most likely not as high as it would by the shoreline.

Physics Talk
-wave: a transfer of energy with no net transfer of mass -medium: the material through which a wave can travel -energy transfers from your arm to the coil -periodic wave: a repetitive series of pulses; a wave sequence in which the particles of the medium undergo periodic motion: that is, after a fixed amount of time, the medium returns to its starting point and then repeats its oscillation -crest: the highest point of displacement of a wave -trough: the lowest point of displacement of a wave -amplitude: the maximum displacement of a particle as a wave passes; the height of a wave crest; it is related to the wave's energy -when there is a large amplitude in a vibrating string, the sound is loud. -wavelength: the distance between two identical points in consecutive cycles of a wave. -frequency: the number of waves produced per unit time; the frequency is the reciprocal of the amount of time it takes for a single wavelength to pass a point -period: the time required to complete one cycle of a wave. -period = 1/frequency -frequency = 1/period -transverse wave: a wave in which the motion of the medium is perpendicular to the motion of the wave. -longitudinal wave: a wave in which the motion of the medium is parallel to the direction of the motion of the wave -standing wave: a wave pattern that remains in a constant position (also called a stationary wave pattern). -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 -compressional waves on a coiled spring are similar to sound waves in air -speed = d/t

Checking Up
1. A wave is a transfer of energy with no net transfer of mass. 2. A transverse wave is a wave in which the motion of the medium is perpendicular to the motion of the wave and a longitudinal wave is a wave in which the motion of the medium is parallel to the direction of the motion of the wave. 3. A node is a point on a standing wave where the medium is motionless and an antinode is a point on a standing wave where the displacement is the largest.

PTG
1a. To find amplitude we measured the distance from side to side in meters. To find wavelength we measured the crest and doubled it because of the trough. To find frequency we found how many times the wave maker's hand went back and forth in one second. To find speed, we found the total distance and divided it by the total time. 1b. Amplitude: meters; wavelength: meters; frequency: Hz; speed: m/s 1c. Amplitude is independent and has no relation to anything. Wavelength and frequency are inversely related. Wave speed is dependent on the medium. 2a. As the coil is shaken more rapidly, wavelength decreases. 2b. Frequency and wave length 2c. Wave speed 3. By measuring from 1 point on a wave to the same point on the next wave 4. You could measure the frequency by counting how many waves are passing and divide it by how long in time the video was. 5a. meters 5b. Hz or Hertz 5c. meters/seconds 5d. wavelength * frequency 5e. wavelength * frequency = speed 6a. A standing wave is a wave that remains in constant position as it follows a pattern. 6b. 6c. You can find the wavelength by measuring one spot on the wave to the same position on another wave. 7a. A transverse wave is a wave in which the motion of the medium is perpendicular to the motion of the wave and a longitudinal wave is a wave in which the motion of the medium is parallel to the direction of the motion of the wave. 7b. Transverse waves move back and forth while longitudinal waves move up and down. 7c. 8a. To decrease the wavelength you would increase the frequency by shaking the string quicker 8b. To increase the wavelength you would decrease the frequency by shaking the string slower 9a. L = n(1/2)lambda 5 = n(1/2)lambda 10/n = lambda 1m, 2m, 3m, 4m, 5m 9b. The frequencies of wave patterns are related to each other because the more wave patterns, the higher the frequency. 10a. 10m 10b. 1Hz 10c. speed = d/t = 20/2 = 10m/s 11a. 3m + 2m = 5m 11b. If the pulses were on opposite sides of the coiled spring you would subtract them and then the amplitude would end up being 1m instead. 12. speed = d/t = 9 / 2.64 = 3.41m/s 13a. trough 13b. 3m 13c. 5m

Physics Plus
a) Amplitude = 4m b) Period = 10seconds/2cycles = 5 seconds / cycle c) Frequency = 2 cycles / 10 seconds = .2Hz d) Wavelength = 8 e) Wave speed = wavelength * frequency = 8m * .2Hz = 1.6m/s

What Do You Think Now
Water moves to make a wave by bobbing up and down vertically, not horizontally. The wavelengths increase as frequency decreases. Since wavelength increases, amplitude also increases since it is directly related to wavelength. Also, the period increases when frequency decreases. Wave speed increases as frequency increases.

=Section 3=

What Do You Think
When you change the tension of a string, the pitch changes because there is a change of mass. The greater the tension, the higher the pitch, and the lower the tension, the lower the pitch. The pitch also changes because tension is a part of vibration.

Physics Talk
-The length of the string determines the wavelength -the higher the pitch, the higher the frequency -wave speed = wave frequency * wavelength -frequency = speed / wavelength -inverse relationship: a relationship in which decreasing one variable increases the other variable or vice versa -decreasing wavelength increases the frequency and pitch -an increase in tension produces a larger force -direct relationship: a relationship in which increasing one variable increases the other variable or decreasing one variable also decreases the other variable -standing waves occur when the length of the coiled spring or string and the wavelength have a particular relationship -length of the coiled spring = a number * the wavelength / 2

Checking Up
1. In the equation "frequency = speed / wavelength" decreasing the wavelength increases the frequency. This occurs because speed does not change, and when the denominator lowers, the answer increases. So since wavelength decreases, frequency increases. 2. The tension of a string is related to its pitch because the the tension increases, the pitch becomes higher. When the string loses tension, the pitch becomes lower. 3. Tension relates to wave speed because the weaker the tension, the slower the wave speed, and vice versa. 4. length of the coiled spring = a number * the wavelength / 2

What Do You Think Now
The pitch changes as tension changes in the string. The greater the tension, the higher the pitch. The lower the tension, the lower the pitch. The tension changes because there is a change of mass. The pitch also changes since tension is a part of vibration.

=Section 4=

What Do You Think
Organs make different pitched sounds by making the sounds come out of different pipes. Some pipes are longer than others, so higher pitched sounds come out of the short pipes and lower pitched sounds come out of the long pipes. On a flute, the sounds come out of the holes on the top that you can put your fingers over. When you cover the holes farther from you, the sounds come out of the holes closer to you. Since the distance the sound travels becomes shorter when you do this, the pitch is higher. If you were to hold the holes closer to you and leave the farther holes open, it would produce a lower pitched sound since the sound would travel farther down the flute.\\

Class Notes
Diffraction- Bending of a wave around an obstacle or through an opening -wavelength must be as big as or bigger than the opening -the bigger the wavelength more bending -the smaller the opening, the more the bending

Physics Talk
-sound is a longitudinal wave -standing waves are set up in the air -at the bottom of a test tube, the air molecules cannot vibrate -the wave's amplitude is zero at the bottom of the test tube -diffraction: the ability of sound waves to spread out or change direction as they emerge from an opening -sound waves travel by spreading out or bending around barriers -the smaller the opening, the more the sound waves diffract -the size of the opening may be determined by the wavelength of the sound wave -the sound you heard when you blew into the straw and across the test tube was produced by a standing wave in the air -if both ends of the straw are open, the air molecules at both ends move back and forth forming a vibrating column of air -when you covered the bottom end of the straw, you prevented the air molecules from moving at the covered end and the pitch and frequency of the sound decreased -wave speed = frequency * wavelength

Checking Up
1. sound travels thorough air through standing waves. 2. sound waves diffract by spreading out or changing direction as they emerge from an opening 3. wavelength multiplied by frequency results in the wave speed. They have a direct relationship with wave speed.

PTG
1a. They are similar since the sounds are all caused by standing waves. Changing the length of the tube and string both change the pitch of the sound. 1b. In one the string moves the air when you pluck and the other you are physically moving the air by blowing. 3a. 11 meters 3b. 3c. 44 meters 3d. Wavelength and frequency are indirectly related. Speed is constant, so as wavelength goes up, frequency goes down and the other way around. 4a. 3*4 = 12 meters 4b. 340/12 = 28.3 Hz 4c. 6 meters 4d. frequency = velocity / wavelength 340 / 6 = 56.6Hz 5. a shorter pipe is going to be a higher frequency. It will be 3x higher. 6a.diffraction 6b. 7. v = d/t 340 = 1600 / t t = 4.71 seconds

What Do You Think Now
Flutes and organ pipes produce sounds certain ways. Organs produce sounds by making sounds go through different pipes. The longer pipes are for lower pitched sounds and the shorter pipes are for higher pitched sounds. When it comes to flutes, there are holes that the sounds come out of. You can cover different holes with your fingers to make higher pitched sounds. When you cover the holes closer to your mouth, the flute makes lower pitched sounds since the air has to travel farther. When you cover the holes farther from your mouth, the flute makes higher pitched sounds since the air does not travel as far.