No More Noise!: How Cotton Density Affects Sound Level in Earmuffs

Voiceover

Presenter(s)(s)

Mary Fernandez

Abstract or Description

This project was about sound barriers. My hypothesis stated that if I use cotton balls (10 grams), a washcloth (15 grams), and a flour sack dish towel (20 grams) to decrease sound in a pair of earmuffs, then the flour sack dish towel will block out the most sound because its greater mass will absorb more noise. I set up the experiment by using cotton balls, 3 cotton washcloths, 3 flour sack dish towels, a kitchen scale, 2 pairs of safety earmuffs, an acrylic cylinder, an acrylic cup lid, a laptop, a Bluetooth speaker, a smartphone, a sound meter smartphone app, duct tape, Scotch tape, and bubble wrap. I found that the less densely packed cotton was better at blocking out the most sound compared to more densely packed cotton. My hypothesis was not supported because the less densely packed cotton worked the best.