Ringing Doorbells

In class, the instructor will have a sound level meter and 5 identical doorbells. The sound level meter measures (in decibels) the intensity level output (how loud the doorbells sound.)

Part 1: Look up decibels in the dictionary. Write down the definition. Do you understand the definition? Write in your own words what you think it means.

The instructor is going to ring first one doorbell, then two doorbells, then three doorbells, etc., until all five doorbells are ringing. After each doorbell is added, we will record the intensity level of sound from the sound level meter.

Part 2: Compared to the reading on the sound level meter of the first doorbell, what do you think will happen to the intensity or the loudness of the sound when there are two doorbells ringing?

Fill in the following table with the number of doorbells and the decibel reading on the sound level meter.

Plot these data points on a graph with the number of doorbells on the x-axis and the decibels on the y-axis.

Part 3: Describe the graph. Is this a graph of any of the functions that we have studied previously? Was the decibel reading for two doorbells twice as large as the decibel reading for one doorbell? How does the decibel reading for five doorbells compare to the decibel reading for one doorbell?