189. A square millimeter (mm) = .000001 of a square meter. A square centimeter (qcm) = .0001 A square decimeter A square meter (m) = = .01 Principal Unit. = = 100 square 10,000 = 1,000,000 = It will be observed that while centimeters are in the second and millimeters in the third decimal place from meters, square centimeters are in the fourth and square millimeters in the sixth decimal place from square meters. 190. In the measurement of land, the square dekameter is called an ar (a), and the square hektometer is called a hektar (ha). 191. Be careful, in converting square measures from one unit to another, to observe that, when the ar is the unit, the point is to be moved as in linear measure; but when the square meter is the unit, the point is to be moved twice as far as in linear measure. Thus, it takes 100 ars to make a hektar; but 100 × 100, or 10,000 square centimeters to make a square meter, and 100 × 100, or 10,000 square meters to make a square hektometer, or hektar. 1. Convert 1,854,276m into hektars; into square kilome ters. 2. How many hektars in 2.7856 square kilometers? 3. Write 1.7431am as square centimeters; as square milli meters. 4. How many square kilometers in 17,467.5 hektars? 5. How many square meters in 1.36149km? 6. How many square meters in 2.25 hektars? 7. How many square centimeters in 0.0137 of a square meter? 8. Write 3.571qem as square millimeters. MEASURES OF VOLUME. 192. The measure of capacity, or volume, is a cube, each face of which is a square unit. Cubic Centimeter, 193. It is to be observed that the cubic meter can be divided into 10 layers, each a meter square and a decimeter thick. Each layer will, therefore, be .1 of a cubic meter. Again, each layer can be divided into 10 equal parts. Each part will, therefore, be .1 of the layer, or .01 of the meter, and will be a decimeter square and a meter long. Also, each one of these parts can be divided into 10 equal parts, each of which will be a cubic decimeter, and will be .1 of .01, or .001 of the cubic meter. The cubic meter, therefore, contains 1000 cubic decimeters. In like manner, each cubic decimeter can be divided into 1000 cubic centimeters, and each cubic centimeter into 1000 cubic millimeters. That is, 194. A cubic millimeter (mm) = 0.000000001 of a cubic meter. A cubic centimeter (ccm)=0.000001 66 66 It will be seen that in cubic measure, the decimal point is to be moved three times as far, when changing the unit, as in linear measure. 195. In measuring wood the cubic meter is called a ster (st). 196. In measuring liquids, grain, etc., the cubic decimeter is always called a liter. If the water in the liter represented in the margin stands 6cm high, how many cubic centi meters of water are there in the measure? How many will be required to fill it? If the faucet be turned and the water allowed to run out until the measure is only half full, how many cubic centimeters will run out? How many will still remain ? Liter Cubic Decimeter. When the liter is the unit, the numeral prefixes have the same value as in linear measure. Thus, 1. How many liters in 1.7cbm? in 157,854ccm ? ПР Liter (common form). 2. How many cubic centimeters in 9.51? in .0151? 3. Change 1.25hl to cubic centimeters; to the fraction of a cubic meter. 4. Convert 431.88' into hektoliters; into the fraction of a cubic meter. 5. Write .375 cbm as liters; as cubic centimeters. 6. Write 734,159.651ccm as liters; as hektoliters; as cubic meters. 7. How many cubic meters in 8,573,412.867ccm ? 8. Change the expression .734578912cbm into cubic centimeters; into liters. 9. Change 1731.5 liters into cubic meters; into cubic centimeters. WEIGHTS. 198. The units of weight are the weights of units of pure Cubic Centimeter. Gram Weight. water taken at its greatest density, that is, a little above the freezing point. The principal unit is the gram, which is the weight of a cubic centimeter of water. The numeral prefixes have the same value as in linear measure. Thus, 200. A cubic centimeter of water weighs a gram. A liter of water weighs a kilogram. A cubic meter of water weighs a ton. 1. How many kilos* in 1.73? in 0.341 of a ton? 2. How many kilos will a hektoliter of water weigh? 3. Convert 13,756mg into grams; into the fraction of a kilo. 4. What is the weight in grams of 346.1ccm of water? 5. Give the weight in kilograms of 0.37615cbm of water. 6. Change .6778kg into milligrams. 7. How many milligrams in the third part of 17.4 grams? *Kilogram is generally called kilo. |