Float, buoyant displacement

A buoyant spherical particle of diameter D floating in a Hquid which has no tendency to wet, ie, pull the shoreline up, or to reject, ie, push the shoreline down, the soHd submerges to a depth d at which the downward force of gravity on the sphere equals the upward buoyancy force of the displaced Hquid. This occurs when... 

Fig. 6.28. Simple float switches (a) buoyant type (b) displacement type...

The buoyant force exerted by a fluid on a floating or submerged body is equal to the weight of the fluid displaced. 

Water-solvent interfacial tension lowering [Figure 18.1(b)]—when the adsorption of a proper surfactant at the liquid-solvent interface results in a marked reduction of the water-displacement liquid tension. In effect, the skin on the water droplet is weakened, the droplet necks down in the presence of agitation, and a significant fraction of primary water droplets is broken away and floated to the surface of the solvent batch due to buoyant forces. 

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