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Determining frequency of sound using a calibrated cathode ray oscilloscope

  1. May 24, 2006 #1
    hi, i have an exam on wave properties in a week. and i found this on the syllabus. i cant remember learning it let alone what a cathode ray oscilloscope is (an electron gun thingymajig?) my textbooks dont explain it well. so if you know how to determine the frequency of sound using a calibrated cathode ray oscilloscope, please help. :eek: :bugeye: :cool: :confused: :surprised
  2. jcsd
  3. May 24, 2006 #2
    A cathode ray oscilloscope is not much different from a voltmeter, except it visually displays voltage (x direction) vs. time (y direction).

    Newer oscilloscopes have nice internal markers on the display, and are calibrated in a way that one can measure the period of the wave, the amount of time for one cycle of the sound wave occurs in.

    Frequency = 1/period. This is how you calculate the frequency of the sound wave.
  4. May 25, 2006 #3
    yay thanks
  5. May 25, 2006 #4


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    Staff: Mentor

    Small typo -- voltage is on the vertical y axis and time is on the horizontal x axis. Here's a link to a popular oscilloscope brand. You will probably recognize the instrument when you see it. To measure the period or frequency of a sound, you would connect your oscilloscope probe to a microphone output, and observe the time waveform on the 'scope display.

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