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Mar 2nd, 2012HW: 5.3 PTG, p 517 #1-5, Due Tuesday Learning Objective
Explain direct and inverse relationships Explain how wave speed, wavelength, and
frequency are related Create a data table to organize data for
experiments. Success Criteria
Describe what determines wavelength and sound
Describe the relationship between tension and speed of a wave
Describe the relationship between wavelength and frequency
Determine the velocity of a wave using the equation
Calculate wavelength of a standing wave Describe how the pitch of the sound produced by
a vibrating string depends on the wave speed, wavelength and frequency of the waves on the string.
Do Now: Finish Vocab
Boxes 5.2 Quiz Write LO and
SC on new left page
WDYS/WDYT on page 508
Agenda Do Now Investigation
5.3 Summary/Exit
Ticket
Mar 2nd, 2012HW: 5.3 PTG, p 517 #1-5, Due Wed. Learning Objective
Explain direct and inverse relationships Explain how wave speed, wavelength, and
frequency are related Create a data table to organize data for
experiments. Success Criteria
Describe what determines wavelength and sound
Describe the relationship between tension and speed of a wave
Describe the relationship between wavelength and frequency
Determine the velocity of a wave using the equation
Calculate wavelength of a standing wave Describe how the pitch of the sound produced by
a vibrating string depends on the wave speed, wavelength and frequency of the waves on the string.
Do Now: Finish data
table and notebook layout for 5.3 #1-7
Agenda Do Now Investigation
5.3 Summary/Exit
Ticket
Investigate
Read procedures 1-7 Lay out notebook and create data
table for #4-6 Make spaces to answer questions 7-
8
Investigate 5.3 (Guidelines for 1-7)
Same set-up as Investigation 1
What kind of wave is the string making?
How do you calculate wavelength?
Standing Wave - this is similar to the waves made in the spring
The wavelength is twice the length of the string
Investigation 5.3 (Guidelines for 8-12)
Complete with your group
Remember that speed is distance traveled over a period of time.
Summary/Exit Ticket
How does changing the wavelength effect the velocity?
How does changing the frequency effect the velocity?
Mar 3rd, 2012HW: 5.3 PTG, p 517 #1-5, Due WednesdaySign up for Honors Meetings!
Learning Objective Explain direct and inverse relationships Explain how wave speed, wavelength, and frequency
are related Create a data table to organize data for experiments.
Success Criteria Describe what determines wavelength and sound Describe the relationship between tension and speed
of a wave Describe the relationship between wavelength and
frequency Determine the velocity of a wave using the equation Calculate wavelength of a standing wave Describe how the pitch of the sound produced by a
vibrating string depends on the wave speed, wavelength and frequency of the waves on the string.
Do Now: If you keep the
wavelength the same, how can you change the velocity of the wave?
Agenda Do Now Notes 5.3 Summary/Exit
Ticket
Physics Talk 5.3
What kind of wave does the vibrating string produce?
How do you calculate the wavelength?
A standing wave
The wavelength is twice the length of the string
Physics Talk 5.3
How does frequency relate to pitch?
Equation for wave speed
The higher the frequency, the higher the pitch
Wave speed = wave frequency x wavelength
Physics Talk 5.3
What happened when you shortened the length of the string?
How is this shown in the equation?
The wavelength was shortened
Pitch increased Frequency increased
Dividing by a smaller number on the bottom, gives us a larger frequency If you have to share
something with fewer people, you get more
http://www.youtube.com/watch?v=HpovwbPGEoo
http://www.youtube.com/watch?v=LDekBnEqTUk&feature=related
http://www.youtube.com/watch?v=n-D3tsZIoZ8&feature=related
http://www.youtube.com/watch?v=YAh4-4UPr64&feature=related
Physics Talk 5.3
What kind of mathematical relationship does this show?
What is an inverse relationship?
Inverse Relationship
A relationship where when one value increases, the other decreases, or as one value decreases, the other increases
Physics Talk 5.3
How is frequency an example of an inverse relationship?
Decreasing the wavelength increases the frequency
Physics Talk 5.3
How are tension and pitch related?
Since the wavelength did not change, and the frequency increased, this means the wave speed increased
An increase in tension, produces a larger force, which leads to a larger acceleration on the string (F=ma)
Physics Talk 5.3
How are tension and pitch related? (continued)
When the force accelerates the string, the wave speed increases and the string vibrates faster
Since the wave is faster, the frequency must also be faster, leading to a higher pitch
Physics Talk 5.3
What is a direct relationship?
Example of direct relationship
A relationship where as one value increases, the other value also increases
Increasing the wave speed also increases the frequency and pitch
Physics Talk 5.3
How does increasing the thickness of the string lead to a different pitch?
When the string is larger, it has a greater mass for the wave to travel through
This also means it takes more force to stop the string from vibrating
The force is the tension in the string
Physics Talk 5.3
How does increasing the thickness of the string lead to a different pitch?
Since the mass is heavier, the acceleration will be less (F=ma)
This creates a slower wave speed
Decreasing wave speed will decrease the frequency and pitch
Physics Talk 5.3
When do standing waves occur?
How does string length related to standing waves?
When the length of the coiled spring or string has a certain relationship
The length much be 1/2, 1, 3/2, 2, etc of the wavelength
Physics Talk 5.3
Equation for standing waves
Standing waves occur when the following equation is met:
L = string lengthn = the number of
antinodes (crests)Lambda = wavelength
Physics Talk 5.3
How do you calculate the period for a wave?
How is a period related to the frequency?
T is the period
The frequency is the reciprocal of the period
LO and SC reflection Learning Objective
Explain direct and inverse relationships Explain how wave speed, wavelength, and frequency are
related Create a data table to organize data for experiments.
Success Criteria Describe what determines wavelength and sound Describe the relationship between tension and speed of a
wave Describe the relationship between wavelength and frequency Determine the velocity of a wave using the equation Calculate wavelength of a standing wave Describe how the pitch of the sound produced by a vibrating
string depends on the wave speed, wavelength and frequency of the waves on the string.
January 19, 2011Sign up for Honors Meetings!
Learning Objective Explain direct and inverse relationships Explain how wave speed, wavelength, and frequency
are related Create a data table to organize data for experiments.
Success Criteria Describe what determines wavelength and sound Describe the relationship between tension and speed
of a wave Describe the relationship between wavelength and
frequency Determine the velocity of a wave using the equation Calculate wavelength of a standing wave Describe how the pitch of the sound produced by a
vibrating string depends on the wave speed, wavelength and frequency of the waves on the string.
Do Now: Finish LO and
SC Reflections Essential
Questions, pg. 516
What does it mean?
How do you know?
Why should you care?
Agenda Do Now Summary Quiz