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Name: Emily
Status: student
Age: 13
Location: N/A
Country: N/A
Date: 1999 


Question:
What is the relationship between the amount of water and object displaces and the weight of the object? Who discovered this theory?


Replies:
Great Question! You are asking about Archimedes Principle, which states: An immersed object is buoyed up by a force equal to the weight of the fluid it displaces.

If the object is floating, then the weight of the fluid (water) displaced is equal to the weight of the object.

If the object is totally submerged, then the weight of the fluid displaced is less than the weight of the object. The object has the same mass, but weighs less in water due to this upward buoyant force acting on it.

For a good explanation of this, look into Paul Hewitt's Conceptual Physics book. He has an excellent explanation of the phenomenon in simplified terms.

---Nathan A. Unterman



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