SI - System International The Metric System

How high is the ceiling?

Is the ceiling 5 glops high? A.Yes B.No

What must be true of any STANDARD ? Universally Understood Repeatable

Old Standards Digit Cubit Foot Hands Stone What is the problem with these Standards?

Metric System Began in French Standardized –What does this mean? Terms to Know –Fundamental / Derived –Quantity / Unit

Fundamental vs Derived Fundamental Units –Base Unit which is defined to be Universally Understood and Repeatable –7 Fundamental Units Derived –A combination of more than 1 fundamental units –Examples: m/s; s 2 ; kgm / s 2 –Often given an equivalent expression: Newton, Watt, Joule

Quantities vs Units Quantities Amount or how much of a specific dimension Examples: Length, Mass, Volume, Density Units Describes the size in which a quantity is measured Examples: meter, foot, inch, mile second, hour, minute, millenium

7 Fundamental Units / Quantities Length - meter Mass - kilogram Time - second Electric Current - Ampere Luminous Intensity - candela Temperature - Kelvin Amount of Substance - mole

Standard Definition - meter Old Definition 1 m is defined as of the distance from the North Pole to the Equator along a line through Lyon, France New Definition (1960) 1 m is defined as times the wavelength of orange-red light from a Krypton-86 lamp Newest Definition (1982) 1 m is defined as the distance light travels in a vacuum in 1/ of a second

Standard Definition - second Old Definition 1 s is defined as 1/86400 of a mean solar day New Definition (1960) 1 s is defined as duration of cycles of the radiation from Cesium-133

Standard Definition - kilogram Old Definition 1 kg is defined as the mass of water at its densest (T= 4°C) which fills a volume of 1.0 liter New Definition (1960) 1 kg is defined as mass of a cylinder of platinum-iridium alloy kept at the International Bureau of Weights and Measures near Paris

Systems of Measurement mks - Meter, Kilogram, Second cgs - Centimeter, Gram, Second fps - Foot, Pound, Second Note: These units are fundamental in that system. What does it mean to be fundamental???

Systems of Measurement Red = Fundamental

Systems of Measurement Red = Fundamental

Systems of Measurement Red = Fundamental

Systems of Measurement Red = Fundamental

Prefixes Large kilok10 3 MegaM10 6 GigaG10 9 TeraT10 12 PetaP10 15 Smaller centic10 -2 millim10 -3 microµ10 -6 nanon10 -9 picop femtof Kids Hate Doing My Dumb Crazy Math