# Sound waves must have intensity if a person is to hear them. a. True b. False

2 months ago

## Solution 1

Guest #4140
2 months ago

a. True

Explanation:

Intensity is what we commonly call Volume, sound waves with no intensity or volume wouldn´t be hearable by humans, so the statement would be True, Sound waves must have intensity if a person is to hear them. The most usual unit to measure sound intencity is Decibels, and  a person with good ears can hear up to -15 dB.

## Solution 2

Guest #4141
2 months ago
A, True

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Applicable formular:

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-a p e x

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I would love to stretch a wire from our house to the Shop so I can 'call' my husband in for meals. The wire could be tightened to have a tension of 240N and a m/L 'weight' of 0.05kg/L. How long would it take for my pulse wave to travel to the Shop (24m) to ring a bell to indicate dinner time.
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