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Sound. If a tree falls in the forest and there is nobody around does it make a sound?. Sound. Disturbance (energy source) Medium (wave travels through) Air Water Steel. Sound. Compression waves travel through air Sound wave are called Longitudinal Waves. Sound in (Medium) Air.
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If a tree falls in the forest and there is nobody around does it make a sound? Sound
Disturbance (energy source) • Medium (wave travels through) • Air • Water • Steel Sound
Compression waves travel through air Sound wave are called Longitudinal Waves Sound in (Medium) Air
Sound can not travel in a vacuum Sound in (Medium) Air
The speed of sound in dry air at 0oC is about 330 meters per second ( 330m/s ) 770 miles per hour mph Speed of Sound
Water vapors in the air increase the speed of sound slightly Speed of Sound
Increase in temperature also increases the speed of sound For each 0oC, the speed of sound in air increases by 0.06m/s Example: At normal room temperature of about 200C sound travels at about 340m/s Speed of Sound
Loudness is sound intensity. The greater the disturbance (intensity) the greater the sound wave Loudness is measured in units of Decibel (dB) Loudness
The transfer of vibration from the primary medium to secondary medium, increasing amplitude Forced Vibration
When an object composed of an elastic material is disturbed, it vibrates at its own special set of frequency, which together forms a special sound. We speak of an object’s natural frequency, which depends on factors such as the elasticity and shape of the object Natural Frequency
When the frequency of a forced vibration on an object matches the Object’s natural frequency, a dramatic increase in amplitude occurs This phenomenon is called resonance. Resonance means to re-sound or sound again. Resonance