63 

 CHAPTER IV 



THE RELATION BETWEEN WEIGHT AND VOLUME 



34. It is a matter of common knowledge that 

 a pound of lead occupies less space than a pound of 

 sugar and that an ordinary brick weighs much less 

 than a lump of iron of the same size. We usually 

 express our realisation of these facts by such phrases 

 as " Lead is heavier than sugar " or " Bricks are lighter 

 than iron". In this chapter we deal with this matter 

 from the standpoint of science by making exact measure- 

 ments of the relation which exists between the volume 

 of a body and its weight. We shall learn that the 

 above expressions are somewhat loose in wording and 

 should more strictly be stated thus : " Lead is denser 

 than sugar " ; " Bricks are less dense than iron ". 



EXPERIMENT 19. Carefully determine the volumes 

 in c.c. of three solid figures made of different materials 

 say lead, iron, and wood by one of the methods 

 previously given. Weigh each body as described in 

 the last chapter. Find the weight in grams of 1 c.c. 

 of each substance by dividing the weight of each body 

 by the corresponding volume. Compare the results 

 obtained in this manner for the weights of equal 

 volumes of the three substances. 



Repeat the experiment with three different solid 

 figures, each made from one of the three materials 

 used previously. Find the weight of 1 c.c. of each 

 substance as before and compare the results obtained 

 with those previously determined. 



If the experiment has been carried out with sufficient 

 care, it will be noted that the weight and hence also 



