Explain the meaning of Buoyant Force (in a liquid) and how it relates to the weight of the object, as well as the weight of the displaced fluid.
The Buoyant Force, supposedly first observed by Archimedes, is the upward force exerted upon a solid in a fluid, and can be expressed as a ratio of densities between the fluid and solid. Density, as you may know, is defined as the mass divided by the volume, or D = m/v. Every solid has a mass and a volume, and therefore the density can be calculated. A solid will float in a fluid if its density is less than that of the fluid; it will conversely sink if its density is more than that of the fluid. Floating implies that the solid displaces a weight of fluid greater than itself; sinking implies it displaces a weight of fluid lesser than itself. Strictly speaking, the weight of an object is not the same as the mass; mass is a singular property expressed in kilograms or pounds; weight is actually a measure of a mass under the force of gravity, given by the formula w = mg, where w is the weight, m is the mass, and g is the force of gravity.