Instrument Frequency Lab

Lab to investigate the mathematical model relating the frequency of a glass instrument to the amount of water inside the glass.

Sound Mini Lab (pdf)
File Size:	405 kb
File Type:	pdf

Download File

---

Sound Mini Lab (editable)
File Size:	59 kb
File Type:	docx

Download File

---

Sound Mini Lab (spreadsheet)
File Size:	10 kb
File Type:	xlsx

Download File

---

---

Video Walkthrough

---

The Tools

 PhyPhox
Free app to allow you access to the sensors in your device. To measure the frequency of a pitch, use the “Audio Spectrum” in the acoustics options

​Microsoft Excel
To record and plot the data with a trendline, it is recommended that you use Microsoft Excel either as an iPad app or the desktop version on a computer

---

Part 1: Collecting the Data

Your lab set up has some choice based on the materials that you have access to. Choose a  method for producing a sound and units for measuring out the water.

Method for Producing Sound (choose one)

• Clinking glass with a knife
• Rubbing finger on glass rim
• Blowing across bottle top

Collect your data by measuring out an amount of water into your container. Create the sound repeatedly using your chosen method and use PhyPhox to measure the peak frequency that is produced. Record your data for four non-zero amounts of water into your spreadsheet and average the three trials for each.

---

Part 2: The Mathematical Model

Create a scatterplot of the amount of water and average frequency columns and add a trendline with an equation. Make sure that the independent variable (amount of water) is graphed on the x-axis. Record this trendline equation as the mathematical model for this system.

---

Part 3: Analysis of the Model

1. What is the slope with units?
2. What is the y-intercept with units?
3. What is the meaning of the y-intercept?
4. Does this model have an upper limit of water amounts that make sense? Why or why not?

---

​Part 4: Testing the Model

1. Choose an amount of water that is different than any of the setups that you used in your data collection
   
2. Use your mathematical model to predict the frequency that will be produced with this amount of water. 
   
3. Measure out this amount of water and use PhyPhox to measure the frequency of the pitch produced
   
4. Calculate the percent error of your model’s prediction
   

---

Click Here for More Labs

---

​Click for more Waves resources ​⬇