Here is an example of a decibel meter. Peak is the highest sound monitored regardless of length of time. Max highest decibel reading over a given time period (depending on the specific meter). Average is the average over the time period the decibel meter has been monitoring sound.
- Now that we have studied sound and how sound travels through the air, what sources produce excessive sound?
- Is there any reasonable way of avoiding these sounds in the urban environment?
- Since we can’t really avoid most of these sounds in the city, what can we do to reduce the intensity of these sounds?
HS-PS4-1. Use mathematical representations to support a claim regarding relationships among the frequency, wavelength, and speed of waves traveling in various media.
HS-PS4-5. Communicate technical information about how some technological devices use the principles of wave behavior and wave interactions with matter to transmit and capture information and energy.*
- Ask the students about the sounds all around us.
- Have examples of stereo speakers, headphones, amplifiers, or point out any public address speakers in your classroom.
- Generate a 60 dB sound at a frequency of 2000 hz.
- Zero the dB monitor and place it inside the box.
- Measure the dB level inside the box.
- Examine the difference in dB level.
- Have the students design a box to reduce the dB level to 50 dB inside.
Students may have not given sound measurement much thought. Sound measurement in decibels is taken over time so when students read a decibel meter and see Peak giving a higher number than Max emphasize the difference being Peak is the highest dB level instantaneously whereas Max is the average highest dB level over time.