1) At a distance of 20.0m from a loudspeaker 1.00E-6J of energy cross your eardrum (Area=0.500cm^2...careful on units!!!!!) in a time of 1.00s. What is the intensity at 100.0m from the loudspeaker?

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Correct Answer: No answer given yet a b c d e

2) A train heads toward you at 30.0m/s and blows its whistle (440Hz when still) as you drive toward the train at 25m/s. What frequency do you observe?

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Correct Answer: No answer given yet a b c d e

3) A standing wave on a string tied at both ends has five nodes (including the ends....draw this). The frequency for this wave is 400Hz. The wave speed is 100m/s on the string. What is the length of the string and fundamental (n=1) frequency.

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Correct Answer: No answer given yet a b c d e