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Question
Give a scientific reason.
We can hear the movement of a mosquito’s wings but we cannot hear the movement of our hands.
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Solution
The frequency of the sound produced by the movement of a mosquito’s wings lies within the human audible range (20 Hz to 20,000 Hz), whereas the sound produced by the movement of our hands has a frequency below 20 Hz, which is inaudible to humans. Therefore, we can hear the movement of a mosquito's wings but not that of our hands.
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