EXERCISE 4 

 HOW MUCH DOES A CUBIC FOOT OF AIE WEIGH? 1 



Materials. The flask used in preceding exercise ; a graduated cylinder (or a foot or metric rule). 



Directions. Ascertain the cubic contents of the container used in the preceding exercise. If the 

 container is spherical the diameter may be measured and the volume calculated ; if it is of any other 

 shape secure the volume by measuring the amount of water necessary to fill it. Considering this 

 to be the volume of the air in the container, and using the difference in weights obtained in the 

 preceding work as the weight of this air, calculate the weight of a cubic foot of air. . 



In your notes explain your method of work, and include in good mathematical form each step 

 in your calculations. 



A liter of air weighs about 1.293 grams. A cubic foot of air weighs 1.29 ounces or 36.61 grams. 

 Knowing these corrected weights, how much error is there in your calculation ? How do you explain 

 the difference ? 



Additional problem. How can you determine the weight of the air in the room in which you are working ? 



1 If the metric units of measurements are desired they may be substituted for the English units. Both systems of 

 measurement should be made familiar by use. 



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