Name: ____________________________________________
Spoon Waves
Today you will be observing what happens when sound waves travel through air vs. a different
medium (yarn). Obtain a large (blue yarn) and small spoon (tan yarn).
Start with the bigger spoon with blue yarn. Hold one end of each piece of yarn so that the spoon
dangles down. Gently swing the spoon so that it taps the desk. What sound do you hear? Is it
what you would expect?
Do it again. Notice how the yarn feels. Do you feel anything?
Now wrap each end of the yarn around your index finger and press the yarn next to your ear
(not IN your ear - no earwax please). What do you hear?
How is the sound traveling through the yarn different from the sound that traveled through the
air?
Why do you think the two sounds are different?
Try the smaller spoon with tan yarn. How does the sound change? Why do you think that is?
Try holding the spoons with different lengths of yarn. Compare and contrast the sounds.
How are the sounds different if you tap the spoon with different materials?
Can you think of an application where this would be useful?
Can you name an invention that uses this information?