2B40.20 - Buoyancy Demo - Archimedes' Principle and Applications

Code Number:
Demo Title:
Buoyancy Demo - Archimedes' Principle and Applications
Archimedes's Principle
Area of Study:
Heat & Fluids
Spring scale (40 N), Bucket (galvanized, small), Rock (large), Pail with spout (4 gal. cap.), Beakers (1000 ml) (several).

Video Credit:  Jonathan M. Sullivan-Wood.

Make sure to pull the plug and equalize the water level in the bucket several minutes before you drop the rock in so that you know that the water you collect is equal to the volume of the rock.  When the rock is dropped in the scale will decrease about 10 Newton's.  Pour the water back into the small bucket and the scale will go back to the starting weight.

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Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.