D J agger, D r e w F rench, and D re w Annett

The speed of sound is about 330 meters per second. Sound waves require some kind of material to travel through. Sound waves can not move through a vacuum. Sound moves through the air at 340m per second. Hard materials can reflect sound so that the sound travels back in the opposite direction, this is called an echo. The faster the vibrations are the higher sound goes, and the slower they go the lower the sound

Sound energy is the energy produced by sound vibrations as they travel through a specific medium. Sound energy is, therefore, a form of mechanical energy. Sound is measured in joules. Puckering, blowing, shaking, beating or scraping can make sounds. Sound is sent out through gases, and liquids as longitudinal waves, also called compression waves.

1. Sound is used to locate fish, find submarines, and measure temperature in the ocean. 2. Bats and dolphins use echolocation which is when sound bounces off an object and back to the animal. 3. Submarines don't have telephone or cable connections, radio signals don't spread underwater, so a submarines relies on sound to send and receive digital data. 4. Sound gives us music. 5. Powerful instruments can have an emotional effect on someone. 6. Sound recordings let us listen to all kinds of music.

 Sound can cause stress and pain.  Dogs can perceive vibrations higher than 20 kHz.  For humans hearing is normally limited to frequencies between about 20 Hz and 20,000 Hz.

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