Standards of Measurement Biology Fall 2016

International System of Units (SI) SI Unit is a system of measurements used worldwide. Several SI base units are used: Kelvin Meter Mole Gram Candela Second Ampere

International System of Units (SI) Length- The distance between two points. Volume- The amount of space occupied by and object. Mass- The amount of matter in an object. Density- The amount of mass per unit volume of a material. Time- The interval between two occurring events.

International System of Units (SI) Meter Quantity Measured: Length Symbol: m A meter is about 3.28 feet Five steps in a staircase The width of a doorway The height of a 5 year old Half the length of a bed The depth of the shallow end of a swimming pool Four rungs up a ladder https://www.mathsisfun.com/measure/metric-length.html

International System of Units (SI) Gram Quantity Measured: Mass Symbol: g A gram is about One paperclip One pen cap A piece of gum The weight of any US bill A GRAM DOES NOT MEASURE WEIGHT! https://www.mathsisfun.com/measure/metric-mass.html

International System of Units (SI) Second Quantity Measured: Time Symbol: s An hour is 60 minutes, and a minute is 60 seconds, so an hour is: 60 × 60 = 3,600 seconds A day is 24 hours so: 1 day = 24 × 60 × 60 = 86,400 second

International System of Units (SI) Ampere Quantity Measured: Electric Current Symbol: A A quantity of charge is measured in units called COULOMBS, and the word Ampere means the same thing as "one Coulomb of charge flowing per second." If we were talking about water, then Coulombs would be like gallons, and amperage would be like gallons-per- second.  http://amasci.com/elect/vwatt1.html

International System of Units (SI) Scientists have produced superheated gas exceeding temperatures of 2 billiondegrees    Kelvin, or 3.6 billion degrees Fahrenheit. Scientists have produced superheated gas exceeding temperatures of 2 billiondegrees    Kelvin, or 3.6 billion degrees Fahrenheit. International System of Units (SI) Kelvin Quantity Measured: Temperature Symbol: K Facts about Kelvin: Water freezes at 273.16 K (That’s 0°C, 32°F) Water boils at 373.16 K (That’s 100°C, 212°F) Absolute Zero is 0 K (Cant get any colder than 0 K) Scientists have produced a superheated gas exceeding temperatures of 2 billion degrees K, or 3.6 billion degrees F! http://www.livescience.com/614-record-set-hottest-temperature-earth-3-6-billion-degrees-lab.html

International System of Units (SI) Mole Quantity Measured: Amount of a substance Symbol: mol When chemists want to have a chemical reaction come out they need to know how many molecules of each kind of chemical they have, so they measure the chemicals in moles. A mole is the atomic weight of a molecule of the chemical in grams. So a mole of a molecule like hydrogen (H) with an atomic weight of 1 is one gram. A complex molecule like glucose (C6H12O6) has an atomic weight of 180, so one mole is 180 grams. Let’s do the math! http://www.qrg.northwestern.edu/projects/vss/docs/propulsion/3-what-is-a-mol.html Carbon: 12(6)=72 Hydrogen: 1(12)=12 Oxygen: 16(6)=96 72+12+96=180

International System of Units (SI) Candela Quantity Measured: Intensity of Light Symbol: cd Superheroes Unite! http://www.nist.gov/public_affairs/kids/kidsmain.htm https://youtu.be/5ZHpOojFtH8

Common SI Prefixes Prefix: Kilo Prefix: Deci Prefix: Centi Example: Symbol: k Multiplying factor: 1,000 Prefix: Deci Symbol: d Multiplying factor: 0.1 Prefix: Centi Symbol: c Multiplying factor: 0.01 Example: Kilometer Kilogram Decisecond Decimeter Centimeter centigram

Common SI Prefixes Prefix: Milli Prefix: Micro Prefix: Nano Example: Symbol: m Multiplying factor: 0.001 Prefix: Micro Symbol: µ Multiplying factor: 0.000 001 Prefix: Nano Symbol: n Multiplying factor: 0.000 000 001 Example: Millisecond Milligram Microgram Micrometer Nanometer nanosecond

International System of Units (SI) Final Thoughts https://www.mathsisfun.com/measure/metric-length.html