7 Which Material is the Best Sound Insulator?

Question: Which material is the best sound insulator? Styrofoam, wood, or drywall.

Hypothesis: I hypothesized that the styrofoam would be the best sound insulator.

Procedure:

• 1. First, I collected my materials. My materials were wood, styrofoam, drywall, sound maker, and a decibel meter.

  2. Next, I made three boxes out of the three materials. I made one out of wood, one out of styrofoam, and one out of drywall.

  3. Then, I got a sound maker, which would be a sound played off of a smartphone.

  4. After that, I used another smartphone which would be used as a decibel meter, because I downloaded an app for it.

  5. I then got my three boxes and kept a control of 60 decibels before placing the sound under the boxes.

  6. I put the sound under the box and recorded the decibels and did that five times for each box.

  7. Then I subtracted the sound after the box was placed over the sound from the control of 60 decibels.

After that, I found my average for each box and found the winner.

Conclusion:

I hypothesized wrong for this experiment. I thought the styrofoam material would be the best sound insulator, but it turned out that the drywall was. I thought the styrofoam would win because I thought it would absorb the sound before it went out. I think my experiment was accurate, but it could have been more accurate. I could have been more precise during my tests. Overall, I thought my project was mostly accurate.

Abstract:

Which Material is the Best Sound Insulator?

By Ava Sorensen

For my science fair project I chose to test which material is the best sound insulator. I tested three different materials; wood, styrofoam, and drywall. I hypothesized that the styrofoam would be the best. I thought the styrofoam would be the best because I thought it would absorb the sound before it tries to travel.

To test my experiment, I needed my materials; which were wood, styrofoam, drywall, a decibel tester, and a sound maker. I used a smartphone for the decibel tester and downloaded an app that would measure sound. I used a sound that I downloaded off of Youtube and played it out of another smartphone. After I got my materials, I made a box out of the wood, styrofoam, and drywall. Each box only had five sides because there was no bottom, since the bottom would be going on a table. Each box was made as if it were going to be used for a house. For example; the drywall was held together with masking tape and glue, the styrofoam was held together with glue, and the wood was held together with nails. After I made the boxes, I tested by placing the smartphones one foot away from each other and recorded how many decibels the sound was without a box over it. I also kept the sound level the same for each test. Then, I placed the box over the smartphone with the sound playing and recorded how many decibels that was. After that, I subtracted the sound decibels before and after the box was placed over the smartphone. After I tested each material five times, I found the averages.

For my experiment I kept a control test of 60 decibels for the sound before placing the boxes over the smartphone. The averages for each material were close in range. The average for styrofoam was 4 decibels. The average for wood was 4.6 decibels. Lastly, the average for drywall was 4.8 decibels. While testing, I found that the averages were really close and I expected the boxes to block more sound than it actually did.

While doing this project I learned that drywall is the best sound insulator for a house. My hypothesis was incorrect because I hypothesized that the styrofoam material would be the best sound insulator, but after I tested it, the drywall was the best. I believe my experiment was accurate, but I could have done it better. It could have been more accurate because instead of an actual decibel meter, I used a smartphone. I decided to use a smartphone instead because the decibel meter is expensive. However; overall I believe that my experiment was accurate.

Wood

Styrofoam

Drywall

Average