Basis Archimedes Principle; Values For 2 Tubes; Values For H2O @ STP; Linear Interpolation Between Tabular Values Produces Up to 15% Error, Values Ignore Eliptical Effect (Assumed Round); Effective Tube Length Stated; Tube and Load Weight Ignored.
Do Not Choose A Tube Based On Bouyancy Alone. A Smaller Tube With A Long Water Line May Have More Bouyancy and Less Friction in the Water. It May Also Have A Higher Rotational Inertia.