As measured from centre ice, a single wildly cheering hockey fan can produce a sound intensity level of 60dB. What sound intensity level would be produced by

Question

20 000 cheering fans?

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If sound waves travel through the ground with an average speed of 6150 m/s and a powerful explosion occurs 5.00kn away, how much time will elapse between when you feel the vibration from the explosion and hear the explosion? Use v=344m/s for the speed of sound in air.

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You pick up two metal rods that look the same and appear to have the same mass. However, when you strike the first rod, it produces a sound that has a much higher frequency than the second rod. What does this result tell you about the speed of sound in the two rods?

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