Term
| What does all waves carry from on location to another? |
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Definition
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Term
| What kind of wave is a sound wave? |
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Definition
| Mechanical wave in which particles move in a medium |
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Term
| Sound cannot travel through a ________ |
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Definition
| vacuum, it must move through a medium |
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Term
| What happens to the molecules in the medium? |
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Definition
| The molecules are alternately compressed (squeezed together) and rarefied (stretched apart) |
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Term
| Sound travels in a ________ line |
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Definition
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Term
| Sound waves are ________ and __________waves |
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Definition
| mechanical and longitudinal |
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Term
| The effects of the medium upon sound wave is called |
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Definition
| Acoustic propagation properties |
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Term
| The effects of the sound wave upon the biologic tissue through which it passes is called |
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Definition
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Term
| What are the 3 acoustic variables of the sound waves? |
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Definition
| Pressure, density and distance |
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Term
| Concentration of force in an area is called |
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Definition
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Term
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Definition
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Term
| Concentration of mass in a volume is |
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Definition
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Term
| What is the unit of density? |
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Definition
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Term
| Measure of particle motion? |
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Definition
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Term
| What is the unit of distance? |
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Definition
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Term
| When is the wave a sound wave? |
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Definition
| when one of the acoustic variable (distance, density and pressure) has a rhythmic oscillation then the wave is a sound wave. |
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Term
| Sound waves are also known as ________ waves |
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Definition
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Term
| How many parameters are used to accurately describe the characeristics of a sound wave? |
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Definition
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Term
| What are the seven acoustic parameter of a sound wave? |
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Definition
| Period, power, propagation speed, frequency, wavelength, amplitude and intensity |
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Term
| What is the wave called when the particles move in a direction that is perpendicular (at right angles) to the direction that the wave propagates? |
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Definition
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Term
| What is the wave called when particles move in the same direction that the wave propagates? |
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Definition
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Term
| When is a pair of waves considered in-phase? |
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Definition
| A pair of waves are considered in-phase when their peaks (maximum values) occur at the same time and at the same location. Similarly, the troughs of the waves (minimum values) occur at the same time. |
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Term
| When is a wave considered out of phase? |
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Definition
| When 2 waves are out-of-phase, their peaks occur at different times, and so do their troughs. |
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Term
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Definition
| More than one sound beam may travel in a medium and on occasion, multiple beams may arrive at an identical location at exactly the same time. The waves lose their individual characteristics at that movement and combine to form a single wave: this combination is called interference |
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Term
| What are the 2 different ways to describe interference of waves? |
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Definition
| constructive interference and destructive interference |
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Term
| What are constructive interference? |
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Definition
| The interference of a pair of in-phase waves results in the formation of a single wave of greater amplitude than either of its components. This combination is called constructive interference, where the resulting wave is larger than eiher of its components |
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Term
| What is destructive interference? |
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Definition
| The interference of a pair of out-of-phase waves results in the formation of a single wave of lesser amplitude than either of its components. This combination is called destructive interference, where the resultant wave is smaller than one of its components. |
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Term
| What happens when there is an interference of waves with different frequencies? |
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Definition
| An interesting phenomenon occurs when waves of different frequencies interfere. At some moment in time, the waves are in phase and the interference is constructive, while at other movments, the waves are out of phase and the interference is destructive. Therefore, when the frequencies of the waves differ, both constructive and destructive interference occur. |
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