Education Technology

# Activities

• ##### Subject Area

• Science: Physics: Sound and Waves

9-12

45 Minutes

• ##### Device
• TI-Nspire™
• TI-Nspire™ CAS
• ##### Software

TI-Nspire™
TI-Nspire™ CAS

1.7

• ##### Other Materials
• Vernier Sound Level Meter
• loudspeaker and sound generator
• meterstick
• copy of student worksheet
• pen or pencil
• blank sheet of paper
• ear plugs (optional)

• By Irina Lyublinskaya

## Sound Intensity

#### Activity Overview

Students investigate the relationship between sound intensity and distance for a commercial loudspeaker. They use collected data to identify a mathematical model for the relationship. They then compare this model with the inverse square law for an ideal point source.

#### Key Steps

• Students should collect a total of ten data points using the methods in steps 7 and 8. A graph of the data points will form on page 1.3 as students collect the data.

• Students should use the Power Regression tool to calculate the best-fit equation for their data set. Note: Some data sets (including the sample data set shown here) may be better fit by a linear function (i.e., y = –x) than by an inverse power function.

• Finally, students should plot the best-fit equation on the graph of the data on page 1.3. They should then answer questions 7 and 8. If you wish and time allows, you may have students repeat the data collection and analysis with different speakers or with a different frequency or intensity of sound.