A boy is listening to the radio. The loudspeaker plays a musical note by vibrating 256 rimes esch second. How many times does the boys eardrum vibrate each second as he listens to the note?

 f_tympanum = 256 Hz.

Explanation:

The eardrum is the vibrating membrane of the human ear, it works by resonance, that is, an external stimulus (force) makes it vibrate, as the eardrum is extremely light it can vibrate at the same frequency of the incident sound.

Consequently if the incident vibration is f = 256 hz, the eardrum resonates at the same frequency

            f_tympanum = 256 Hz.

As a reference the response of the eardrum goes from f = 20 Hz f = 20000 Hz

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