EE: how is the molecular structure of porous materials ideal for sound absorption

[hazemm]

[size=3]hey guys,

I am currently in my second year of IB, and haven't even started my extended essay. At the end of last year I proposed a research question which i though would work out, which was how does the elasticity of a material affect its ability to reduce noise, but I found this to broad. Over the summer I started thinking about the specifying my research question more, so I decided that id focus on sound absorption. Therefore my current research question is how is the molecular structure of porous materials ideal for sound absorption. I can test this by building a a wooden tunnel in an L shape and lining it with different porous materials ie carpet, Styrofoam, fibreglass. one end of the tunnel would have a speaker producing a specific frequency note, or even a tuning fork, and at the other end have a recorder, which will then allow me to analyse the sound file on different audio meters and frequency plugins on my computer, and compare it with the orginal frequency. I could also look at this through a theoretical point of view if i can calculate how much acoustic energy is absorbed by the different materials i shall be testing. If anyone could give me some advice here or just comment on my research question( does it make sense, is it narrow enough)or the experiment(whether it seems practical and scientific enough for IB standards). Oh and if u have any suggestion on a research question which i could base my EE in feel free to add hahaha.

thanks

hazem[/size]

Edited September 9, 2008 by hazemm