1K20.70 - Falling Bottle Capstan

Code Number:
Demo Title:
Falling Bottle Capstan
Friction, Simple Harmonic Motion
Area of Study:
String with Sand filled bottle on one end and #6 stopper on the other (Capstan App).

Hang the apparatus over a horizontal rod in an Atwood's arrangement and show that the sand filled bottle is much heavier than the stopper.   Then pull the sand filled bottle close to the rod by pulling on the stopper.  Lift the stopper to an angle of 15 to 20 degrees above the horizontal rod. When you let go of the stopper, the bottle will fall about 1/2 to 2/3's the length of the string before it is stopped by the wrapping action of the stopper around the horizontal rod.

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