Shorter sounds Will a short straw clarinet have a higher or lower pitch than a longer one? Blue team 4th Grade Mrs. Johnson Northview Elementary School
Statement of the Question We will make ‘clarinets’ out of straws. Which clarinet will make the highest sound, the short one or the longer one?
Project Overview • Many of us have just begun to play an instrument, so we are curious about how an instrument produces different pitches. We will make ‘clarinets’ our of straw and will vary the length of them to see how if affects the pitch.
Research The most important ideas from our research were: • Sound is created by vibrations. These vibrations create waves that travel to our ears and make our eardrum vibrate as well. • The highness or lowness of a sound is called its ‘pitch’. • The ‘frequency’ of a sound refers to the number of waves that travel per second. The ‘wavelength’ refers to the distance between the top of one wave to the next. • The shorter the wavelength, the higher the frequency. • Objects with shorter wavelengths create higher pitches than objects with lower wavelengths.
Variables • CONTROLLED variables – these variables will be kept the same: - type of straw - method used to make ‘clarinet’ - musician • INDEPENDENT variable – this variable is the one we changed on purpose: - length of straw
Variables, continued • Independent variable - the pitch made by the straw, high or low V
Prediction or Hypothesis These are the predictions of our class: - 17 students said the shorter straw will sound higher because shorter instruments, like piccolos tend to make higher sounds than longer instruments, like trombones. - 8 students said it would sound the same because changing the straw length should have nothing to do with the sound produced. - One student noted that when she tested her clarinet reed, the same sound was produced as when she had her entire clarinet assembled.
Materials • 1 straw for each student • Scissors • rulers
Procedure • 1. Each student will create a clarinet by cutting a V shape on one end of the straw. • 2. Without shortening the straw, students will blow on the end and observe the pitch. • 3. Students will shorten straw to 2 inches. • 4. Student will blow on straw and compare the pitch to the first straw.
Data/Observations • Of our 26 students, only 8 were able to producesound on their clarinets! The other 18 will continue to practice! • Of these 8 students, ALL reported a higher pitchwhen they shortened their straws.
Conclusion All 8 of our clarinets sounded higher when shortened. So we can conclude that a shorter object does make higher sounds than a longer one. We are still not sure why a higher frequency of sound waves results in a higher sound. We might like to investigate this question in future STEM fair projects.
Works Cited Kids Konnect website: 2012. Online. 10 Sep. 2012. Available: http://www.kidskonnect.com Mahaney, Ian. Sound Waves. New York: Rosen Classroom, 2007. Science for Kids website: 2012. Online. 10 Sep. 2012. Available: http://www.sciencekids.co.nz Trumbauer, Lisa. All About Sound. New Haven: Children’s Press. 2004