Measurements and Units

Long Ago… Parts of the human body were often used to measure. The length of the king’s foot or the distance from the tip of his nose to his fingertips were both common units of measurement.

Problems Which is a basketful? It would often change as soon as a new king was crowned It was different from country to country Which is a basketful?

SI system (metric system) – a standard unit of measurement 1790 (metric system) – a standard unit of measurement All scientists everywhere can share and replicate the same data. Now used in nearly every country in the world except the United States.

Metric System throughout the World Gray – countries that only use the metric system Red – countries that don’t use the metric system (U.S., Liberia, Burma)

What is the Metric System? There is only one base unit for each thing measured Length = meter Mass = gram Volume = liter

Measuring Length English System Metric System inch, foot, yard, mile meter Whether you are measuring the length of your finger or the length of the Nile River, you always use meter.

Measuring Mass or Weight English System Metric System ounce, pound, ton gram Whether you are measuring the mass of a nickel or the mass of a car, you always use gram.

teaspoon, tablespoon, cup, pint, quart, gallon Measuring Volume English System Metric System teaspoon, tablespoon, cup, pint, quart, gallon liter Whether you are measuring the volume of a glass of water or the volume of a swimming pool, you always use liter.

Compare the difference English System Metric System teaspoon, tablespoon, cup, pint, quart, gallon liter ounce, pound, ton gram inch, foot, yard, mile meter 13 words 3 words

How big are they? METER – a little longer than a yard (1.1 yards) LITER – a little larger than a quart (1.06 quarts) GRAM – about the mass of a paper clip

What about measuring really big or really small things? In the English system, we would use inches But in the metric system, since the meter measures everything, it is broken up into smaller units and prefixes are added to the word “meter.”

Measured in multiples of 10 Prefix - represent the multiples of 10 decimeter “deci” = .1 or 1/10 centimeter “cent” = .01 or 1/100

Basic Unit of Measurement (grams, liters, meters) 6 common prefixes: Prefix Symbol Factor Number Kilo- k 1,000 Hecto- h 100 Deka- da 10 Basic Unit of Measurement (grams, liters, meters) Deci- d 0.1 Centi- c 0.01 Milli- m 0.001

Kilo- Symbol = k Number = 1000 kilometer kiloliter kilogram 1000 meters 1000 liters 1000 grams

Hecto- Symbol = h Number = 100 hectometer hectoliter hectogram 100 meters 100 liters 100 grams

Deka- Symbol = da Number = 10 dekameter dekaliter dekagram 10 meters 10 liters 10 grams

Meter, Liter, Gram Symbol = m, l, g Number = 1 meter liter gram length volume mass or weight

Putting the 2 symbols together Kilo = k meter = m Kilometer = km Hectogram = hg Kiloliter = kl

Deci- Symbol = d Number = .1 (tenth) decimeter deciliter decigram

Centi- Symbol = c Number = .01 (hundreth) centimeter centiliter centigram .01 meter .01 liter .01 gram

Milli- Symbol = m Number = .001 (thousanth) millimeter milliliter milligram .001 meter .001 liter .001 gram

Basic Unit of Measurement (grams, liters, meters) 6 common prefixes: Prefix Symbol Factor Number Factor Word Kilo- k 1,000 Thousand Hecto- h 100 Hundred Deka- da 10 Ten Basic Unit of Measurement (grams, liters, meters) Deci- d 0.1 Tenth Centi- c 0.01 Hundredth Milli- m 0.001 Thousandth

Practice h = m = c = k = d = da = If I give you the symbol, you give me the prefix h = m = c = k = d = da =

Practice kilo = hecto = deka = centi = milli = deci = If I give you the prefix, you give me the number kilo = hecto = deka = centi = milli = deci =

Practice mg = cl = hm = dg= dal = km = If I give you the symbols, you give me the word mg = cl = hm = dg= dal = km =

Practice deka = kilo = milli = deci = hecto = centi = If I give you the prefix, you give me the symbol deka = kilo = milli = deci = hecto = centi =

Practice What is the base unit for length? What is the base unit for mass or weight? What is the base unit for volume?

Even if you live in the U. S Even if you live in the U.S., you're using the metric system—probably without realizing it. Your home computer might have several megabytes of memory and a few gigabytes of storage. Mega- and giga- are prefixes used in the metric system. Mega- stands for "one million," so a megabyte is a million bytes. Giga- stands for "one billion." If computing continues at the rate it's been going, we may soon be talking about petabytes—one million billion bytes.

About 15 years ago, Congress passed a law saying that all consumer products had to include both English and metric measurements