fairfolio
Saved Projects

Can You Hear Me Now?

CSEF · 2005 Physics & Astronomy

Nicole Kowtko · Woodside Elementary School, Woodside

Overview

Objectives/Goals I want to determine the relationship between air pressure and sound. I hypothesize that as the air pressure decreases, the sound will decrease at a faster rate. Methods/Materials A ringing bell was placed inside a vacuum chamber, along with a digital sound level meter. For each test cycle, I increased the vacuum gauge 5 inches of mercury of vacuum at a time, from 0 to 25. (This decreased the air pressure in the vacuum chamber.) I recorded the inches of mercury of vacuum and the corresponding decibel number from the sound meter. After five tests, I reviewed and evaluated my data. Results For each of my tests, the decibels consistently decreased as the air pressure decreased. In particular, the decibels decreased in larger increments every time there was an increase of 5 inches of mercury of vacuum. Conclusions/Discussion Based on my test data, I have reached the conclusion that the decibels and inches of mercury of vacuum have an inverse relationship. You can also say that sound level decreases quickly with decreased air pressure. Either way, there is a logarithmic pattern. In other words, the decibels decrease at a rate that is exponential and not linear.

Summary statement

My project is about identifying the relationship between air pressure and sound, by adjusting the air pressure in a vacuum chamber, while the sound remains constant.

Help received

My mother helped me with Excel and gave me lots of support and advice. My science teacher helped review my work. My math teacher tried to figure out a pattern to my test results, and my two neighbors patiently taught me about the vacuum chamber.

Awards (1)

  • Category Award

Competition history

  • CSEF 2005 Physics & Astronomy · Entry J1520

Resources

Related projects

Closest projects by meaning, across every fair and year in the corpus.

Browse more like this

Source: California Science & Engineering Fair public projects

Save projects to your library

Sign in with Google to keep track of projects you find interesting, organized into folders. An account also raises your daily allowance for “Has this been done?”, and lets you create a key for the MCP server with a much higher limit than anonymous use. Browsing stays public.

Continue with Google