The setup for the lab is similar to the one shown above.  We used a Pasco mechanical vibrator to provide the oscillations.  The mechanical vibrator was driven by a Pasco digital function generator-amplifier, model number PI-9587.  The mechanical vibrator was originally set up so that the rod was parallel to the table.  The gravitational force that was exerted on the rod was negligible because it was constant, so no force was added to the elastic load introduced by the vibrator.  However at higher frequencies, some difficulties arose with the resulting torque on the mechanical vibrator introducing a lateral vibration of the rod.  We moved the apparatus into the position shown above, eliminating the torque on the vibrator.  The strobe light was used to aid the picture taking process.  A schematic of the setup for the hoop of wire is shown below.

 

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