PURPOSE: To determine the speed of sound in air.
DESCRIPTION: A series of pulses from the oscillator is input into a small loudspeaker and picked up by a microphone. The oscilloscope is triggered by the pulses to the loudspeaker but displays the signal from the microphone. If the microphone is moved away from the loudspeaker, the signal picked up by the microphone will be delayed in time, shifting to the right on the scope. The speed of sound is the distance the microphone is moved divided by the time shift of a pulse on the oscilloscope. P>
REFERENCES: (PIRA 3B30.10)
EQUIPMENT: Wave generator, small loudspeaker and microphone mounted on optical rail, amplifier, and oscilloscope with dual trace plug-in.
SETUP TIME: 10 min.
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