1. A Brief History of Measurement

2. Ancient Measures 4 Early man used parts of the body like a forearm, hand, foot, or finger for length measurements. 4 To measure volume, they would fill the container with seeds and count the seeds. 4 As scales were invented, seeds and stones were used as standards. These were not consistent standards. 4 Each society had their own measurements which made it hard for trade.

3. English Measurement 4 Tradition says that King Henry I of England decreed that his foot would become the official measurement for a foot of length and that a yard would officially be the distance from the tip of his nose to the end of his outstretched thumb.

4. 4 Through royal decrees, England developed a better standardized measurement system than most other countries at that time. 4 There was however no relationship between the different measurements of volume, mass and length and they all have different base units. 4 One cannot easily convert from one measure to another without division or multiplication English Measurement

5. English Customary Measures 4 Length = 12 inches =1 foot, 3 feet = 1 yard 5280 feet = 1 mile 4 Mass = 1 pound = 16 ounces 4 Volume = 1 gallon = 4 quarts, 1 quart = 2 pints What a mess!!!

6. Science and Trade needed a better system 4 The metric system originated in France. 4 It is based on units of 10 which allows conversion by just moving a decimal point. 4 The base units for this system are –Meter (m) for length –Liter (L) for volume –Gram (g) for mass

7. 4 Kilo = 1000 base units 4 Centi=1/100 base unit 4 Milli =1/1000 base unit Metric Prefixes

8. International System of Units 4 In 1960, an international committee simplified the metric system into 7 basic units called SI units. –Length =Meter (m)Mass = Kilogram (kg) –Time = Second (s)Temperature = Kelvin –Amount = Mole (mol) Current = Ampere –Candela = Luminous Intensity 4 From these 7, all other units can be derived.