EXERCISE 54 

 WHAT IS THE LIFTING EFFECT OF WATEK UPON AN OBJECT IMMEKSED IN IT? 



Materials. The stone used in the preceding exercise ; balance ; cup large enough to contain the 

 stone ; small cord. 



Directions. Dry the stone and weigh it. Suspend it from a balance by a thread in such a manner 

 that the stone is immersed in water but does not touch the side or bottom of the vessel. Weigh 

 while in water. Fill out the following table : 



Weight of stone in air 



Weight of stone in water 



Loss of weight in water 



Weight of water displaced 



Volume of water displaced (1 cc. = 1 g.) 



Volume of stone 



Weight of one cubic centimeter of stone 



Stone is how many times heavier than equal volume of water 



Study this table and make a short, clear statement of the important facts you discover. 



Additional problems. Is the method of determining volume as given in this experiment more or less 

 accurate than that of the preceding experiment ? 



If the density of an object is the weight of a unit volume of the object, what is the density of the 

 stone used in the above experiment ? 



It has often been noticed that, when bathing, one can lift a large stone from the bottom to the top 

 of the water, but cannot lift it above the surface. Why is this ? 



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