Chapter 5, Section 1

Sounds in Vibrating Strings

2/13/2012HW: 5.1 PTG #1-5, pg. 490 Due

Wed• Learning Objective:

– Describe the relationship between pitch, frequency, tension, and sound.

– Write a conclusion that includes IV, DV, evidence, and the big idea.

• Success Criteria:– Observe the effect of string

length on the pitch of the sound produced

– Observe the effect of tension on the pitch of the sound produced

– Control the variables of tension and length

– Summarize experimental results

• New Seats• Do Now:

– Read Chapter Challenge pg. 480-481

– Write LO and SC on a new left-side page

– WDYS/WDYT pg. 484

• Agenda:– New Seats– Do Now– Investigate

Investigate• Read #1-5 pg. 485-486• Create data table to record data from

experiment

Length of Vibrating String(measure from the center of the cup to the pulley)

# of 500g hanging masses Pitch (high, medium, low) High pitch sounds like the squeal of a vehicle’s brakesLow pitch sounds like the rumble of thunder

20cm 120cm 220cm 440cm 140cm 240cm 460cm 160cm 260cm 480cm 180cm 280cm 4

Summary – Record Answers in Notebook

• When you increase the mass (add weights) to the string, the tension on the string increases. What happens to the pitch?

• When you increase the distance between the cup & the pulley, but keep the mass the same, what happens to the pitch?

2/14/12HW: 5.1 PTG #1-5, pg. 490 Due

Wed• Learning Objective:

– Describe the relationship between pitch, frequency, tension, and sound.

– Write a conclusion that includes IV, DV, evidence, and the big idea.

• Success Criteria:– Observe the effect of string

length on the pitch of the sound produced

– Observe the effect of tension on the pitch of the sound produced

– Control the variables of tension and length

– Summarize experimental results

• Do Now:– Look at your conclusion

for 6b from yesterday. Does it have:• IV and DV• Evidence/Data• Big Idea

– What happened to the pitch as you changed the length of the string?

– What happened to the pitch as you changed the mass on the hanger?

• http://www.youtube.com/watch?v=LOL8-qIYemg

• http://www.youtube.com/watch?v=SK52EVv9xew&feature=related 

• http://www.youtube.com/watch?v=5V_hWBRZKuk&NR=1&feature=fvwp

•  

• http://www.youtube.com/watch?v=r2BOApUvFpw

• http://www.youtube.com/watch?v=z_lwocmL9dQ

• http://www.youtube.com/watch?v=fW97YtogQvE

• http://www.youtube.com/watch?v=2L8lVLcfJ0s

Physics Talk• Read pg. 486-487• Complete 2 column notes in

notebook• Be sure to define– Vibrate– Variable– Pitch– Frequency – http://www.freemosquitoringtones.org/

Essential Questions-pg. 489• In your notebook answer the–What does it mean?– How do you know?–Why should you care?

• Be prepared to discuss in your group

PTG #1-5, pg. 490