WARNING Science can ALWAYS CHANGE based on new

WARNING! • Science can ALWAYS CHANGE based on new observations, knowledge, and understanding.

What is Science? • Science has many branches. • Biological science is the science of living things. • Physical science is the science of matter and energy. • Earth science is the science of the Earth, the atmosphere, and weather. • Science is the knowledge obtained by observing natural events and conditions in order to discover facts and formulate laws or principles that can be verified or tested.

Science & Technology • Science and technology work together. • Some scientists practice pure science defined as the continuing search for scientific knowledge. • Some scientists and engineers practice applied science defined as the search for ways to use scientific knowledge for practical applications. • Technology is the application of science for practical purposes.

Science & Technology Example: When did scientists begin learning about bacteria & other very, very tiny organisms? =Science Invention of Microscope in 1600’s. =Technology When were scientists able to make them? When they had developed an understanding of optics and light. =Science

The International System of Units or S. I. (Also known as the metric system)

Why S. I. ? • All scientists use the International System of Units to make sharing data and results easier • Abbreviated SI for the French phrase, Le Système Internationale d’Unités • SI units are used for consistency amongst scientists • Much easier to use than the English System • Metric system (S. I. ) is based on multiples of TEN How many kilometers are in a mile?

Countries Not Using S. I. • Three countries haven’t gone metric… – USA – Liberia – Burma

Problems with Two Systems • In 1999, $125 Million Mars Lander crashed • Problem was due to one group using English Units to make a calculation & another group using Metric Units • Important to use same system for consistency • Important to communicate

SI Base Units All other units are derived from the 7 base units below such as volume, velocity, density, etc. • • • Measurement Length Mass Time Temperature • Electric current • Amount of substance • Luminous intensity Unit Abbreviation Meter m Kilogram kg Second s Kelvin K Ampere Mole Candela A mol cd

(S. I. )Metric Prefixes for Large Measurements • Prefix • Giga • Mega • Kilo- Symbol G M k Meaning Mult. Of Base Power billion 1, 000, 000 109 million 1, 000 106 thousand 1, 000 103 Since KILO means 1000, think of kilometer as 1000 meters. MEGA means 1 million, so think of a megabyte as 1 million bytes, and so on.

(S. I. )Metric Prefixes for Small Measurements • Prefix • • • Symbol Meaning Mult. Of Base Power Decid tenth 0. 1 10 -1 Centi- c hundredth 0. 01 10 -2 Millim thousandth 0. 001 10 -3 Micro- millionth 0. 000001 10 -6 Nano- n billionth 0. 00001 10 -9 Since CENTI means 1/100 (or 1 one hundredth), think of centimeter as 1 one hundredth of a meter; millimeter (1/1000) as 1 one thousandth of a meter, etc.

(S. I. )Metric Conversion Chart 1000 kilokm 100 k. L hecta- kg hm 10 h. L deca- 1 hg dam home da. L base dag meter (m) 0. 1 Liter (L) deci- gram (g) dm 0. 01 d. L centi- dg cm 0. 001 c. L milli- cg mm m. L mg

Practice • • • 1. 2. 3. 4. 5. 1. 85 m = ______cm 3. 5 km = ______cm 4. 6 km = ______ mm 298 m = ______ km 455 cm = ______km

Exit Ticket #1 Questions 1 -4 • 1. What is the SI base unit for mass? – A. – B. – C. – D. Meter Kelvin Kilogram Kilometer

• 2. What is the prefix that means thousand? – A. – B. – C. – D. Centi. Kilo. Mega. Milli-

• 4. Why is it important to use the same system of measurement in science? – A. – B. – C. – D. Consistency Communication Makes sharing data and results easier. All of the above.