52 FIRST YEAR COURSE IN GENERAL SCIENCE 



If a tank is 50 cm. x 40 cm. X 30 cm., its capacity is 60,000 

 cu. cm., and the weight of water contained in the, tank, when 

 full, is 60,000 grams or 60 kilograms. If the liquid were 

 twice as heavy as water, its weight 

 would be 120 kilograms. (LABORATORY 

 MANUAL, Exercise IV.) 



50. Measurement of Capacity. 

 A box measuring 10 cm. (or 1 dm.) 

 on each inside edge has a volume of 

 1,000 cu. cm. (or 1 cu. dm.). The 

 amount of liquid it will hold has 

 been named the liter (pronounced 

 leeter), which is about one quart. 

 Liquids and gases in large quantities 



cm. i. How many grams are measured by the liter. Fractions 

 would i cu. dm. of water of the liter are usually expressed as 

 cubic centimeters or as the decimal of 

 a liter; as, 275 cu. cm. or .275 of a liter. 



1 g. 1 cu. cm. 



FIG. 17. MEASURES 

 OF WEIGHT 



A small box 1 cm. on 

 edge would have a volume 

 of 1 cu. cm. and would 

 hold 1 g. of water. A 

 1-gram weight made of 

 brass or iron would not 

 be so large as 1 cu. 



weigh? 2. What prefix 

 could be used instead of 

 the number of grams? 

 3. One pound is equal 

 to the weight of about 

 450 g. How many 

 pounds in 1 kg.? 



1,000 cu. cm. is always 1 liter, but 

 1,000 cu. cm. of a liquid does not always 

 weigh 1 kilogram. 

 1,000 cu. cm. of water is 1 liter of water and weighs 1 kilogram. 

 1,000 cu. cm. of sea water is 1 liter of sea water and weighs about 

 1.025 kilograms. 



1,000 cu. cm. of sulphuric acid is 1 liter of sulphuric acid and weighs 

 1.8 kilograms. 



51. Inertia. A book resting on a table will never change 

 its own position; a ball thrown on smooth ice will go a long 

 distance in a straight line before it stops. This inability of 

 a body to change its own state of motion or rest is called 

 inertia. If a body is at rest, it tends to remain at rest; if 

 it is in motion, it tends to continue in motion in a straight 

 line with unchanging speed. 



Illustrations of this law of inertia are seen in moving cars. 



