4. A train sounds its horn as it approaches an intersection. The horn can just be heard at a level of 50 dB by an observer 10 km away (Treat the horn as a point source and neglect any absorption of sound by the air). (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 50 m from the train?

4. A train sounds its horn as it approaches an intersection. The horn can just be heard at a level of 50 dB by an observer 10 km away (Treat the horn as a point source and neglect any absorption of sound by the air). (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 50 m from the train?

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter14: Sound

Section: Chapter Questions

Problem 21P: A train sounds its horn as it approaches an intersection. The horn can just be heard at a level of...

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