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In: Physics

2. From a vantage point very close to the track at a stock car race, you...

2. From a vantage point very close to the track at a stock car race, you hear the sound emitted by a moving car. You detect a frequency that is 0.852 times smaller than that emitted by the car when it is stationary. The speed of sound is 343 m/s. What is the speed of the car?

3.Hearing damage may occur when a person is exposed to a sound intensity level of 90.0 dB (relative to the threshold of human hearing) for a period of 9.00 hours. An eardrum has an area of 2.71 x 10-4 m2. How much sound energy is incident on the eardrum during this time?

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