An underwater robot used in marine archaeology is immersed in seawater (density p = 1025 kg/m,...

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An underwater robot used in marine archaeology is immersed in seawater (density p = 1025 kg/m, bulk modulus B = 2.37 109 N/m). This robot is equipped with a sonar that emits ultrasound at a frequency of 200 kHz with a pressure amplitude Ap1 = 179 Pa. When the ultrasound encounters an artifact (a stationary substance) with a bulk modulus B = 10.34 1010 N/m, and an impedance Z > Z, the sonar-detected sound intensity level of the reflected wave is IL2 = 99.2 dB. a) Calculate the impedance Z and determine the sound intensity level IL1 with which the sonar emits. b) Calculate the impedance Z and the volumetric mass density p of the artifact. c) What is the speed of ultrasound in the substance from which the artifact is made, and identify this substance from the following table: Substance Rubber Lead Concrete Gold Bronze Brass Iron Glass Granite Speed of sound (m/s) 70 1905 3100 3240 3400 3508 4529 5300 6200 d) If 1 = 0, determine the wave function Apr (x, t) of the pressure acoustic wave reflected by the artifact. e) If the robot approaches the artifact and perceives a beat frequency of 292.5 Hz between the wave it emits and the echo it receives, determine the speed in km/h at which the robot is approaching the artifact. An underwater robot used in marine archaeology is immersed in seawater (density p = 1025 kg/m, bulk modulus B = 2.37 109 N/m). This robot is equipped with a sonar that emits ultrasound at a frequency of 200 kHz with a pressure amplitude Ap1 = 179 Pa. When the ultrasound encounters an artifact (a stationary substance) with a bulk modulus B = 10.34 1010 N/m, and an impedance Z > Z, the sonar-detected sound intensity level of the reflected wave is IL2 = 99.2 dB. a) Calculate the impedance Z and determine the sound intensity level IL1 with which the sonar emits. b) Calculate the impedance Z and the volumetric mass density p of the artifact. c) What is the speed of ultrasound in the substance from which the artifact is made, and identify this substance from the following table: Substance Rubber Lead Concrete Gold Bronze Brass Iron Glass Granite Speed of sound (m/s) 70 1905 3100 3240 3400 3508 4529 5300 6200 d) If 1 = 0, determine the wave function Apr (x, t) of the pressure acoustic wave reflected by the artifact. e) If the robot approaches the artifact and perceives a beat frequency of 292.5 Hz between the wave it emits and the echo it receives, determine the speed in km/h at which the robot is approaching the artifact.