Two sets of ultrasonic rods

 

Code Number: 3C20.16

Demo Title: Ultrasonic Waves - Suspended Rods , Ultrasound

Condition: Good

Principle: Audible Frequency Range of the Human Ear

Area of Study: Oscillations &Acoustics, Biology

Equipment: 

Two sets of ultrasonic rods and a striker.

Procedure:

Strike the rods on the end with the striker.  The shortest rod should have a frequency of 30 KHz which is well above the human range of hearing.  The longest rod should be within the range of human hearing.  With this set the limits of audition can be tested.

A microphone on the oscilloscope can be used to show that sound is still emitted from the bars that you cannot hear.

References:

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