Introduction to the Metric System Reviewing Measurement Systems

Introduction to the Metric System Reviewing Measurement Systems and Metric System Resource: Ms. Grogan

History l Created during French Revolution in 1790 l French King overthrown l National Assembly of France sets up new government l French Academy of Science told to design new system of weights and measures l Lavaiosie appointed to head committee l

History l Called l Systeme International d’Unitès, or SI - International System of Units l Revised l periodically by International Bureau of Weight and Measures

Customary Units of Measurement l The English System l a collection of functionally unrelated units l l l Difficult to convert from one unit to another Ex. 1 ft = 12 inches = 0. 33 yard = 1/5280 miles Customary Units l l length - inch, foot, yard, mile weight/mass - ounce, pound volume - teaspoon, cup, quart, gallon temperature - degrees Fahrenheit time - minutes, hours

Advantages of Using the Metric System l Universal - used everywhere by all scientists to communicate l by all industrialized nations l except United States l U. S. loses billions of dollars in trade l

Advantages of Using the Metric System l Simple l to use A few base units make up all measurements length - meter l mass - grams l volume - liters l temperature – degrees Celsius l time - seconds l

Advantages of Using the Metric System l There is only one unit of measurement for each type of quantity l To simplify things, very small and very large numbers are expressed as multiples of the base unit. l l Prefixes are used to represent how much smaller or larger the quantity is compared to the base unit. Easy to convert from one unit to another l l shift decimal point right shift decimal point left

Advantages of Using the Metric System l Same set of prefixes for all units l Greek - multiples of the base l l Latin - fractions of the base l l kilo - 1000 × the base hecto - 100 × the base deka - 10 × the base deci - tenths of the base centi - hundredths of the base milli - thousandths of the base Mnemonic: “Kids Have Dropped Over Dead Converting Metrics. ”

Metric Prefixes

Units of Length l Length - the distance between two points standard unit is meter (m) l long distances are measured in km l l Measured using a meter stick or ruler

Prefixes and Units of Length l centimeter - cm l l l millimeter - mm l l l 1 m = 100 cm 1 cm = 1/100 th m 1 m = 1000 mm 1 mm = 1/1000 th m 10 mm = 1 cm measures very small lengths kilometer - km l l l 1 km = 1000 m 1 m = 1/1000 th km measures long distances

Measuring Mass l - the quantity of matter in an object standard unit is gram (g) l Measured using a digital scale or triple beam balance

Measuring Volume and Capacity l Volume - the amount of space occupied by an object standard unit is liter (L) l 1 L = 1000 ml = 1000 cm 3 = 1 dm 3 l Measured using a graduated cylinder l l Capacity - a measure of the volume inside a container

Prefixes and Units of Volume l Liter - L l l l milliliter - m. L l l l 1 L = 1000 milliliters 1 L = 1000 cubic centimeters = 1000 cm 3 measures small volumes 1 m. L = 1 cubic centimeter 1000 m. L = 1 Liter 1 m. L = 1/1000 th liter kiloliter - k. L l l measures large volumes 1 k. L = 1000 L

Measuring Time l metric unit is second (s)

Measuring Temperature l Temperature the degree of “hotness” of an object l l standard unit is celsius (°C) measured with a thermometer

Temperature Conversions Conversion Between Fahrenheit, Celsius, and Kelvin l Example: l l l Convert 75 ºC to ºF Convert -10 ºF to ºC