College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 37

The speed of sound in steel is about 4.50 km/s. A steel rail is struck with a hammer, and an observer 0.400 km away has one ear to the rail. (a) How much time will elapse from the time the sound is heard through the rail until the time it is heard through the air Assume that the air temperature is 20 °C and that no wind is blowing. (b) How much time would elapse if the wind were blowing toward the observer at 36.0 km/h from where the rail was struck