Determine the Archimedean force acting on a cork lifebuoy with a volume of 30 dm³ if it is 1/3 submerged in water.

V = 30 dm3 (cubic decimeters) – the volume of the cork lifebuoy;

ro = 1000 kg / m3 (kilogram per cubic meter) – density of water.

It is required to determine F (Newton) – the Archimedean force acting on the lifebuoy if it is immersed in water by 1/3 of its volume.

Let’s translate the units of measurement of volume in the SI system:

V = 30 dm3 = 30 * 10-3 = 3 * 10-2 = 0.03 m3.

Find the volume of the submerged part of the lifebuoy:

V1 = V * 1/3 = 0.03 / 3 = 0.01 m3.

Then the Archimedean (buoyancy) force will be equal to:

F = ro * V1 * g, where g = 10 Newton / kilogram (approximate value);

F = 1000 * 0.01 * 10;

F = 10 * 10 = 100 Newtons.

Answer: a buoyant force equal to 100 Newtons acts on the lifebuoy.