A cup or two should do it,
but the container would have to be a real precision fit.
If the object is less dense than water, the water will be able to keep it afloat. If the object is more dense than water, the water will not be able to keep it afloat, and it will sink.
It means to keep from sinking a fluid such as water. To keep afloat.
It is to keep a plant or seaweed afloat on water.
They are filled with air, which is less dense than water, therefore keeping you afloat.
Being able to use the turbulence in the water to help them stay afloat is one adaptation that the plankton has to keep themselves afloat. They also use structures near the surface of the water to help them.
It's hair on the leaves.
An armband is an inflatable band worn around the arms in order to keep afloat in water.
You can keep afloat a number of ways in deep water. By swimming any of the four key strokes, Front Crawl, Backstroke, Breaststroke and Butterfly, or by simply treading water. Also, it is possible to float on your back. If you keep still enough, the buoyancy of the water will prevent you from submerging, especially if you take a breath.
The swim bladder keeps the fish upright in water.
When the ship sank I used a lifebelt to help me keep afloat.
tail
Israel. The Dead Sea.