Sound: Feel the Vibration
Today we discussed sound and learned that sound travels in longitudinal waves, transmitting the vibrations of an object through a medium (solid, liquid, or gas) to our ears, where our brain interprets the pressure waves as various tones. Interestingly enough, sound, unlike light, requires a medium to travel through and while we often hear loud explosions during space battles in SciFi movies, this is not scientifically possible because in the vacuum of space there is no medium for the sound wave to move through.
Through a series of activity stations, students got to experience firsthand how sound moves differently through different materials, and how factors such as string tension & thickness and pipe length affect the pitch of sounds in musical instruments. Using simple instruments (rubber-band banjos, pipes, and glass harps), we studied how the vibrations each instrument made were related to its pitch (frequency) and volume (amplitude). We also learned that sound travels better through solids, than liquids or gases. Ask your student why this is true (due to the tightly packed atoms of a solid being able to transmit the vibrations or sound wave better). Students had a blast making noise and learning about sound compression waves!
Throw on a pair of headphones and check out this fun video to test how “old” your ears are: How Old Are Your Ears from ASAP Science https://www.youtube.com/watch?v=VxcbppCX6Rk