Science+Fair+WP

=Hypothesis:Acoustic foam is the best sound insulator.= = = =Materials:= Decibel meter wood sound insulator

=Info:= Casella Decibel Meters to decibel waves Sound is measured in decibels When sound bounces of flat walls it takes longer to reach the ear. A diffuser spreads the sound
 * Speed of sound in various mediums ||
 * Medium || Speed in feet per second || Speed in meters per second ||
 * Air at 59 degrees F. (15 degrees C) || 1,116 || 340 ||
 * Aluminum || 16,000 || 5,000 ||
 * Brick || 11,980 || 3,650 ||
 * Distilled water at 77 degrees F. (25 degrees C) || 4,908 || 1,496 ||
 * Glass || 14,900 || 4,540 ||
 * Seawater at 77 degrees F. (25 degrees C) || 5,023 || 1,531 ||
 * Steel || 17,100 || 5,200 ||
 * Wood (maple) || 13,480 || 4,110 ||

This chart and information is from: []
 * Terms used in the study of sound ||
 * Acoustics is the science of sound and of its effects on people. ||
 * Condensation is a region in a sound wave in which the sound medium is denser than normal. ||
 * Decibel (dB) is the unit used to measure the intensity of a sound. A 3,000-hertz tone of 0 dB is the softest sound that a normal human ear can hear. ||
 * Frequency of a sound is the number of sound waves that pass a given point each second. ||
 * Hertz is the unit used to measure frequency of sound waves. One hertz equals one cycle (vibration, or sound wave) per second. ||
 * Intensity of a sound is a measure of the power of its waves. ||
 * Loudness refers to how strong a sound seems when we hear it. ||
 * Noise is a sound that is unpleasant, annoying, and distracting. ||
 * Pitch is the degree of highness or lowness of a sound as we hear it. ||
 * Rarefaction is a region in a sound wave in which the density of the sound medium is less than normal. ||
 * Resonance frequency is the frequency at which an object would vibrate naturally if disturbed. ||
 * Sound medium is a substance in which sound waves travel. Air, for example, is a sound medium. ||
 * Sound quality, also called timbre, is a characteristic of musical sounds. Sound quality distinguishes between notes of the same frequency and intensity that are produced by different musical instruments. ||
 * Ultrasound is sound with frequencies above the range of human hearing—that is, above 20,000 hertz. ||
 * Wavelength is the distance between any point on a wave and the corresponding point on the next wave. ||

The Bose L1® Model II system with B2 bass is a good speaker. because of the very high tension range on the speakers.

where //P//in and //P//out are the input and output powers respectively. A similar calculation can be done using a [|natural logarithm] instead of a decimal logarithm, and without the factor of 10, resulting in [|nepers] instead of decibels:
 * ~ dB ||||~ power ratio ||||~ amplitude ratio ||
 * > 100 ||> 10 000 000 000 ||  ||> 100 000 ||   ||
 * > 90 ||> 1 000 000 000 ||  ||> 31 623 ||   ||
 * > 80 ||> 100 000 000 ||  ||> 10 000 ||   ||
 * > 70 ||> 10 000 000 ||  ||> 3 162 ||   ||
 * > 60 ||> 1 000 000 ||  ||> 1 000 ||   ||
 * > 50 ||> 100 000 ||  ||> 316 || .2 ||
 * > 40 ||> 10 000 ||  ||> 100 ||   ||
 * > 30 ||> 1 000 ||  ||> 31 || .62 ||
 * > 20 ||> 100 ||  ||> 10 ||   ||
 * > 10 ||> 10 ||  ||> 3 || .162 ||
 * > 6 ||> 3 || .981 ||> 1 || .995 (~2) ||
 * > 3 ||> 1 || .995 (~2) ||> 1 || .413 ||
 * > 1 ||> 1 || .259 ||> 1 || .122 ||
 * > 0 ||> 1 ||  ||> 1 ||   ||
 * > -1 ||> 0 || .794 ||> 0 || .891 ||
 * > -3 ||> 0 || .501 (~1/2) ||> 0 || .708 ||
 * > -6 ||> 0 || .251 ||> 0 || .501 (~1/2) ||
 * > -10 ||> 0 || .1 ||> 0 || .316 2 ||
 * > -20 ||> 0 || .01 ||> 0 || .1 ||
 * > -30 ||> 0 || .001 ||> 0 || .031 62 ||
 * > -40 ||> 0 || .000 1 ||> 0 || .01 ||
 * > -50 ||> 0 || .000 01 ||> 0 || .003 162 ||
 * > -60 ||> 0 || .000 001 ||> 0 || .001 ||
 * > -70 ||> 0 || .000 000 1 ||> 0 || .000 316 2 ||
 * > -80 ||> 0 || .000 000 01 ||> 0 || .000 1 ||
 * > -90 ||> 0 || .000 000 001 ||> 0 || .000 031 62 ||
 * > -100 ||> 0 || .000 000 000 1 ||> 0 || .000 01 ||
 * An example scale showing power ratios //x// and amplitude ratios √//x// and dB equivalents 10 log10 //x//. It is easier to grasp and compare 2- or 3-digit numbers than to compare up to 10 digits. ||

From What is a Decibel. The speed at which sound propagates (or travels from its source) is directly influenced by both the medium through which it travels and the factors affecting the medium, such as altitude, humidity and temperature for gases like air. Bad news for Star Wars fans—there is no sound in the vacuum of space because there are too few molecules to propagate a wave. It is important to note that sound speed in air is determined by the air itself. It is not dependent upon the sound’s amplitude, frequency or wavelength. To calculate the speed of sound in dry air at sea level, use the following formula:

**V = 331.4 + 0.6Tc** V = velocity (m/s), Tc = temperature in Celsius.
 * Use the interactive Speed of Sound calculator below to see the effect of temperature on sound's velocity. ||

For comparison, the speed of light in a vacuum is 299,792,458 meters per second or 186,000 miles per second (669,600,000 mph), which is roughly 870,000 times faster than the speed of sound. The difference between the speed of light and the speed of sound is why you see lightening before you hear it (unless you are struck by it, in which case it may be simultaneous!). As a comparison with sound in other mediums, the speed of sound in helium at 0°C is approximately 972 meters per second (m/s), or around 3 times as fast as in air. Sounds travels even faster in liquids and solids because of their greater density (although standard measurement is slightly more complicated because of it is effected by the shape of the material and also the fact that both longitudinal and transverse waves may propagate in solids). Sound in 20° C water travels an average of 1482 m/s, while sound in aluminum travels at 6420 m/s. Modern navies depends heavily on being able to predict the speed of sound in varying water conditions for their SONAR echo-location systems.

If you have ever lived in an apartment with shared walls and a party next door, you are no doubt aware that sound waves can transfer from one medium to another and back again—in this case from air to the rigid wallboard and back to air again. The speed with which it travels changes accordingly with the shift in mediums. A wide variety of sound isolation products and construction techniques attempt to mitigate this sort of transfer. For further sound-abatement information, see Auralex's Acoustics 101.

It is important to realize that while all sound in the equivalent conditions travels at the same speed, whether louder or softer, higher or lower, the speed or force of the individual molecules bumping into one another increases with amplitude and/or frequency. Pg 218 and 219 Sound and music in The New Way things work by David Macaulay =Works Cited:= Casella. "Sound Level Meters." //Casella CEL in the UK //. Casella Measurement, 2013. Web. 24 Sept. 2013. .
 * This is a good website because this is an actual company that makes and engineers decibel meters.

"DB: What Is a Decibel?" //DB: What Is a Decibel? // N.p., n.d. Web. 02 Oct. 2013. .
 * This a school for the physics on sound.

"Gain." Wikipedia. Wikimedia Foundation, 19 Aug. 2013. Web. 29 Sept. 2013. []


 * This is a good Source because it is linked to some audiologists.

"How Fast Does Sound Travel?" How Fast Does Sound Travel? N.p., n.d. Web. 05 Oct. 2013. []
 * This is a good site because it is a college

"L1® Model II System with B2 Bass." Bose. N.p., n.d. Web. 25 Sept. 2013. .
 * This is a good website because they engineered the products.

"Sound." HowStuffWorks. N.p., n.d. Web. 25 Sept. 2013. .
 * This is a good source because Science.com is a international known name because different scientists use it for there research.

Macaulay, David, Neil Ardley, and David Macaulay. //The New Way Things Work //. Boston: Houghton Mifflin, 1998. Print. Pg 218-219 Sound