ACCORDING TO THE VARIABLES
The smaller the mass within a volume of water – lets say a bucket – the less space it is likely to take up with air.
In simple terms, the density of a small stone is heavier than a larger cork. The stone will always sink, and the cork will float. This is because each has a different mass of substance – it’s individual units – from whatever each is made up of. The cork, being organic, has far lighter weight within it’s structural design, than that of a stone usually formed of heavier minerals. eg. Quartz. Understanding density in this example here is due to the molecules of the cork, as against those of the stone plus all mass volumes of water in the bucket.
Even in a larger volume of water, such as a river, massive tree trunk logs will float, because of the heavier concentration in the volumes of the water. Added to this is also the strength of the energy found in the flow of the water. Water will keep afloat compounds of such nature, so long as the volume of it’s own weight in water, outweighs its carrier; but only up to the point of this bearer (as the log,) becoming saturated, when it will sink. Yet a cork would need a heavy weight to sink it.
We ourselves being 70% water, would have to be able to expand our oxygen levels to remain afloat. Naturally we would sink in a smaller volume, where our own collective denseness would not hold us afloat in a lesser amount of water. Its own distribution en mass would be totally outweighed. We would be like an adult pig trying to float in a bathtub.
When it comes to any lake or a sea, the quantity of water would be greater than ourselves; and filling our lungs with as much oxygen as possible, we could have knowledge of how to stay afloat. If we became as an empty bag filled with water; our mass weight would be close to equal, our density likewise to that of the water, and we would automatically sink. Like water, we would find our own gravity.
The same dynamics must be taken into consideration to keep a dug-out canoe floating. Within it’s weight of one, two or five people on board, it must balance, and not become too heavy in mass to allow it’s rim becoming lower than the water line. Again, gravity would become the balancing act within the displacement of the total weight, as against the filling up of the empty hollow of the dug-out.
Though the lake or sea here would be a much heavier density in volume; once the weight of the water filled the hollowed areas of such a canoe – especially if a storm tossed it on the waves – they would be equal in mass once full, and thus sink.
Some have added riggers – rafts – to help counteract the balance of this happening. But even where the amount of water is by far the greater mass, the water-line would still measure the density; and be the measurement of its mass collection. The canoe could no longer replace it’s own space in the water in which it is supposed to float.
When it comes to floating, density = mass + volume, and water will always have the upper hand unless there is another distribution to counteract. This is when ballasts are placed at their given strategic points depending on the weight of what must remain afloat. One could even say one weight must balance the other to improve stability when afloat. As equally as a plane must utilize the densities of air in which to stay air-bound.
It is this buoyancy which is the counter-balance in understanding the density of the medium in which something must float, such as water. When a log counteracts it’s own weight just its state of balance between the elements within it, as against that of the water’s density and volume of the water, it is its own ballast.
When a ship becomes a city of steel and every other considered structure, it must counteract its float just as the biggest jumbo jet in the sky. It must use its mass weight; ballast its buoyancy with counter-weights; and the seas which have enough volume to counteract everything around and within it, to keep it afloat. Its massive displacement of water must be in absolute balance to it’s medium.
Whatever the natural, or the engineering, needed to keep afloat, it is as equally as a submarine needs its balloons called buoyancy’s equilibrium for underwater. Gravity is all part of the buoyancy act. It like a cloud which can rise no higher, before dropping its cargo of rain. In short the density we must understand lies according to the variables which must stay afloat; when even a grain of sand can sink..
Yet it’s a paradox when density is measured just in the salts of the Dead Sea’s water content. Impossible to sink; and very much against gravity when trying to dive in!