Ch5-KistB

Bryan Kist's Wikilog - Period (6) CP Physics - (E. Burns) - 2010

toc =Chapter 5=
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=Section 1= what do you see - there is a can attached to a string and it is making noise like a guitar what do you think - they change the tensions of the string and have different places to pluck the strings from in order to change the pitch. they would have their fingers as close to the pick ups as possible in order to make the highest pitch.

Physics Talk - Vibrating is when an object moves back and forth rapidly - Pitch is how high or low a note is in music - The two variables that effect the pitch is the length and the tension of the object - as the tension of an object increases, so does the pitch - the shorter the object is the faster it will vibrate and the higher the pitch will be

Checking up 1. The pitch gets higher when the tension increases 2. Pitch increases when the length of a string decreases 3. it gave the string greater tension increasing the pitch 4. the objects that are struck vibrates, and the area of the surface being struck will have an effect on the pitch

Inquiring Further - Hearing Essay
 * 1) 3- Evelyn Glennie is special because she is deaf, but has spent years developing her sense of touch in order to determine the pitch. Sound is not actually a "sound" but rather a vibration that our ear drums sense and out brain makes sense of what it is. Since sound is a vibration, hearing is basically a sense of touch and feeling. She says when there are low vibrations, she can feel it in her legs and feet, but if it is a higher pitch she can feel it in her chest, shoulders, and face. she says that she is not completely deaf, but profoundly deaf. This means she can still hear but it can not be made out clearly

Physics To Go 1. a. you can change the tension of a spring by adding or decreasing the weight on the end of the string b. when you add weight, this increases the tension of the spring, which means that there is going to be a higher frequency and a higher pitch.

2. a. you can put your finger down on the fret changing the pitch during a performance b. changing the length means that there will be a higher frequency.

3 a. The way you can change the tension and keep the same pitch is to either make the string longer or change the mass b. you can change the length of the string the same and keep the pitch the same is by changing the tension of the string or change the mass

4. if you changed both the tension and the length, the sound would change much more than if you were to only change one of them.

5. a. the player plays different notes by changing the length of the string by pushing on it with their fingers b. they change the pitch to tune it to make sure that it is not sharp or flat, meaning that if it is to high or to low for that specific note, they need to change the tension to make it in tune

6. a. the purpose of the nobs on the end of a guitar are to make each string tunable, this happens by changing the tension on each string to make it play in tune b. guitars need tuners because over time and after being played, each string may not have as much tension as it did when it started making it out of tune. c. the pitch gets lower because the strings stretch so you would be flat

7. a. the frets on the guitar are designed to show the players where they need to place their fingers to play a certain note on a certain string by making it longer or shorter b. violins and cellos do not have frets but the pitch is changed by the player using their fingers c. they need more accuracy because they do not have frets, meaning that they need to make sure their fingers are in the right place more than a guitarist.

8.

Physics Plus

1+2.

3. When you increase the mass of the string, frequency decreases which means a lower pitch 4. the thicker ones have a larger mass and are longer than the high pitch ones and that is so the piano has a wider range of sounds than other types of instruments.

What do you think now - they make different sounds by changing the tension of the string and the length of the string by using their fingers. when they increase the tension and decrease the length, there is going to be a higher frequency. when they decrease tension and increase length they are going to have a lower pitch.

=Section 2= What do you see- there is a wave and there is a girl surfing on it, which means that there are similarities between waves and water What do you think- the motion of the water is parallel to the the bottom of the ocean, so as it gets closer to the shore, it is seen as a wave

Physics Talk - Wave is a transfer of energy with no net transfer of mass - medium is the substance that carries the wave - frequency is the number of waves for 1 period of time - period is the number of seconds for 1 wave - wave speed is the speed of the wave, this can be calculated as d/t - a pulse is 1 single disturbance - waves happen over and over again - the crest is the highest point of displacement on a wave - the trough is the lowest point of displacement on a wave - amplitude is the maximum displacement of a particle as a wave passes - wavelength is the distance between 2 identical points in consecutive cycles of a wave - A Transverse wave is a wave that in which the motion of the medium is perpendicular to the motion of the wave - A Longitudinal wave is when the motion of the medium is parallel to the motion of the wave - A standing wave is a wave pattern that remains in a constant position - Node is a point on a standing wave where the medium is motionless - destructive interference - anti-node is a point on a standing wave where the displacement is the largest - constructive interference - THE MEDIUM IS THE ONLY THING THAT EFFECTS THE SPEED OF THE WAVE - the number of anti-nodes is called a harmonic - N/lambda= length of the string - Fundamental = the 1st harmonic - interference is a property, and it is when 2 waves are in the same place at the same time - destructive interference is when a crest meets with a trough, and constructive is when the crest meets with a crest or a trough with a trough

Checking up 1. a wave is a transfer of energy with no net transfer of mass 2. in transverse waves the motion of the medium is perpendicular, and in longitudinal the motion is parallel 3. a node is a point where the medium is motionless, and the anti-node is a point where the displacement is largest.

Physics Plus



Class Question frequency= .2Hz period=5s wave speed= 1.6m/s amplitude= 4m Wave length= 8m

PTG 1a. we measured the amplitude by stretching the coil out to 10, 20, and 30cm's, wavelength by using the measuring tape, and wave speed by doing distance divided by time b. we used Meters for amplitude, Meters for wavelength, and Meters per second for wave speed c. wave length and wave speed are related because wave speed uses meters, and length is measured in meters 2a. when you shake the coil faster, frequency increases, making the waves shorter b. wave speed, and length change c. amplitude does not change 3. you can measure it by taking the distance from one point on a wave, to the same point on the next wave 4. the frequency is the number of waves in a certain time, so you can find out how many waves occurred in that time and divide by the number of seconds 5a. Meters b. Hertz c. M/s d. Wavelength times frequency e. Meters*1/s=m/s 6a. a vibration of a system in which some particular points remain fixed while others between them vibrate with the maximum amplitude. b. c. You can find the wavelength by measuring from one anti-node, to the next 7a. longitudinal waves are ones where the energy is parallel to the medium and a transverse wave is one where the energy is perpendicular to the medium. 7b. Coiled springs can be both, transverse if moving side to side, or longitudinal by moving it forward an backward 8a. To make the wavelength shorter increase the frequency by shaking faster b. make the length longer by shaking it slower, and decrease the frequency 9a. 5 meters - 2.5 meters - 1.67 meters - 1.25 meters - 1 meter b. The frequency and the wave patterns are related because the more waves, the higher the frequency 10a. 20 meters b. The period is 2- so the frequency is 1/2Hz c. V=d/t, V=5m/s 11a. they would be 5m since you add b. if they were going opposite, it would be 1m since you subtract 12. d/t=9/2.6= 3.41 13a. nodes b. 6m c)

What do you think now - the waters energy moves up and down, but since the wind makes it move from side to side it is a transverse wave

= Section 3 = What do you see - there are 2 people and they are both playing string instruments, one is playing a harp and the other is playing with a broom stick, the name of the show is standing waves What do you think- the pitch changes when you increase the tension of the string because when there is a greater tension, there is a higher frequency meaning a higher pitch

Physics Talk - length of a string is always 1/2 of the wavelength of the lowest frequency standing wave - Wave speed= Wavelength*Frequency - decreasing the wavelength, increases the frequency and the pitch - Frequency= Velocity / wavelength - increasing the wave speed, increases the frequency and pitch - Length= (N*Wavelength)/2, where N= the number of anti-nodes in a standing wave

Checking up 1. the smaller the wavelength the higher the frequency 2. higher tension means a higher pitch since it accelerates faster 3. higher tension means higher frequency 4. L=(n*lambda)/2

What do you think now - pitch changes when you change the tension of the spring because the wavelength decreases meaning that there has to be a higher frequency and a higher pitch

= Section 4 = What do you see- there are 4 people, they are all playing wind instruments, one has a bottle, another has a tuba type thing, another has a straw, and the girl has a blade of grass What do you think- flutes and pipe organs make their sounds by producing a standing wave inside the pipe, the longer the pipe, the lower the pitch, the shorter the pipe, the higher the pitch

Physics Talk - Sound is a compressional wave - the vibration at the end of an open tube is what makes the sound we hear - diffraction is the ability of sound waves to spread out or change direction as they emerge from an opening - a smaller opening creates more diffraction than a larger opening - the size of the opening can be determined by the wavelength of the sound wave

Checking up 1. Sound travels through air as a compressed wave 2. waves diffract by bouncing off something or traveling through an opening 3. V=Wavelength*Frequency, and if the wave speed stays the same, one must get proportionally smaller as the other gets larger

Physics To Go 1 a. both the string and the pipe produce waves b. the string is a transverse wave while the pipe has a compression wave

3 a. the longest pipe in a pipe organ is 11m b. IN NOTEBOOK c. L=n*.25*lambda 11=.25lambda 44m=lambda d. a large wavelength indicates a low frequency because there is only one antinode

4 a. 3*4= 12m long b. V=f*wavelength 340=12f Frequency= 28.3Hz c. it is 6m since it is double d. 340=6f frequency= 56.7Hz

5. its frequency is greater since you are dividing the speed by a smaller nimber

6. a. this phenomenon is called diffraction b.IN NOTEBOOK

7 a. 340=1600m/t t=4.71s