Floatation

For an object  to float in a liquid , the density of the liquid is higher than the density of the object

For a floating object U=Mg

From archimede’s principle

Upthrust =volume of liquid displaced  X  Density of liquid=weight of the liquid displaced.

U=Mg

The weight of a floating  object is equal to the weight of the liquid displaced.

This is known as

The Principle of Floatation

, which states that:

A floating body displaces its own weight from the liquid in which it floats  

OR

The principle of floatation states that a body floats when the upthrust is equal to the weight of the body.   See fig 1 above.

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