Buoyancy OU: Virtual water displacement test
An inverted Travis Effect is examined. The big cup is placed on the scale and tared to zero. The “pod” cup — the TE displacer — is lowered into position to displace some volume in the big cup. Water is poured between the cups to fill the outer cup to the brim. The scale weight is noted to be 380 grams. Then the “pod” cup is removed and the scale weight is noted to be 203 grams. This confirms the “negative buoyancy” effect. But where does the “extra” weight come from? When I fill the cup up with water to the same level, but without the inner pod… the scale measures the same as it did before, with the pod in place — 382 grams (To within experimental error cause by spillage, clingage, and etc.) Thus… the “extra” weight isn’t extra at all, it merely represents the weight of the “virtual” displaced water…. a weird concept in itself.