# Sound Pipe Lab

## Question:

How will changing the length of a plastic pipe change its sound (period) when struck on your palm?

## Background:

Example: Our instructor showed us how striking the open end of a 6" plastic pipe on his palm makes a pleasing sound. It sounded a little like a wood block I've used in band in middle school, only more "airy". I know that larger bells have a lower tone when struck. The larger pipes on pipe organs also have a lower tone than the small pipes.

## Prediction/Hypothesis:

If the length of the pipe is _________ then the pipe period should be _________ because sound period is longer (frequency is lower) with larger structures.

Be specific! If the length is doubled then the period will be one-half what is was...

## Equipment:

• Several lengths of pvc pipes from the hardware store (6", 9" 12")
• A way to measure the sound frequency such as the Soundcard Oscilloscope

## Procedure:

1. Have the instructor setup the Soundcard Oscilloscope
2. Students provide the rest of the procedure.

## Data:

 Trials Pipe length = cm Pipe length = cm Pipe length = cm Trail 1 Trail 2 Trail 3 Average period (s)

## Conclusion:

1. Restate the prediction or hypothesis.
2. Clearly state whether the prediction/hypothesis was correct or give a correct answer to the investigative question.
3. Provide the range of data from high to low.
4. Explain how the data supports or rejects the hypothesis or answers the question.