A train sounds its horn as it approaches an intersection. The horn can just be heard at a level of 47 dB by an observer 10 km away.
(a) What is the average power generated by the horn?
(b) What intensity level of the horn's sound is observed by someone
waiting at an intersection 43 m from the train? Treat the horn as a
point source and neglect any absorption of sound by the air.
A train sounds its horn as it approaches an intersection. The horn can just be heard...
a train sounds its horn as it approaches an intersection. The horn can just be heard at a level of 40dB by an observer 10 km away. a) what is the average power generated by the horn? b) what intensity level of the horn's sound is observed by someone waiting at an intersection 58m from the train? Treat the horn as a point source and neglect any absorption of sound by the air.
6)Two adjacent natural frequencies of an organ pipe are determined to be 912 Hz and 1008 Hz. (Assume the speed of sound is 343 m/s.) (a) Calculate the fundamental frequency of this pipe. Answer must be in Hz (b) Calculate the length of this pipe. Answer must be in m 7)A train sounds its horn as it approaches an intersection. The horn can just be heard at a level of 60 dB by an observer 10 km away. (a) What...
A light-rail commuter train blows its 200 Hz horn as it approaches a crossing. The speed of sound is 337 m/s. (a) An observer waiting at the crossing receives a frequency of 221 Hz. What is the speed of the train? m/s (b) What frequency does the observer receive as the train moves away? Hz
phons 100 9 80 60 A 40 20 20 10k 1000 100 10 Frequency Hz) a) At approximately what frequency is the human ear most sensitive? How can you tell? b) If you heard a 300-Hz tone with a sound level of 60 dB, approximately how many phons would you perceive? toward you with a speed v, starting a distance of 1 km away att 0. If the train moves very slowly (that is, v is extremely small compared to...
1. The speed of sound in an alcohol at a temperature of 20°C is 1260 m/s. The density of the alcohol at that temperature is 650 kg/m^3. At a temperature of 20°C, find the bulk modulus of the alcohol. 1030 MPa 1080 MPa 1140 MPa 1190 MPa 1240 MPa 2. During a thunderstorm, you hear the sound 4 s after you see the lightning flash. How far did it fall? Assume the temperature outside is approximately 20 1.324 km 1.372...
I am completing a study guide for the next section of class because I am trying to get ahead. Any suggestions? A wave whose displacement velocity is either in the same direction or opposite direction as the wave velocity describes which type of a wave? a. Transverse wave b. Mechanical wave c. Longitudinal wave d. Electromagnetic wave Which of the following are always one wavelength apart and are drawn as parallel lines? Plane waves b. Wave fronts c. Wave phase...