What is the acoustic propagation speed (m/sec) of sound waves in standard liquid water?
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Answer: A. 1500
Explanation
Acoustic propagation speed depends on bulk modulus and fluid density. Sound waves travel through standard liquid water at approximately 1500 meters per second. High liquid incompressibility results in much faster sound speeds than in gases. Speed of sound is the square root of isentropic bulk modulus divided by density. Water has a high bulk modulus, making it resistant to volumetric compression. Temperature and dissolved impurities alter the exact acoustic propagation speed in water.
Sonar and underwater navigation systems rely on accurate acoustic speed values in water. Water hammer transient pressure wave calculations require precise acoustic wave speeds. Oceanographers map marine trench depths using echo-sounding acoustic propagation times. 330 meters per second represents the approximate speed of sound in air, not water. 1000 meters per second underestimates the true bulk modulus stiffness of liquid water. 3000 meters per second overestimates standard acoustic velocities at room temperature.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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