1. Chapter 1 Lesson 2 “The Scientific Method” Key Concepts… What is the scientific method? What is the SI System? Why should we learn the SI System?

2. I. What is the Scientific Method? (Ex. Pg. 13) A. An organized plan used to help solve a problem. B. The General Idea… -Use your senses. “The lights went out in my room…” -What do you want to know? “What caused the lights to go out?” -Find out any information. “Check to see if other lights work.” -Make an educated guess using what you already know. “The lights went out because ___________.” Observations Ask a Question Research Form a Hypothesis

3. -Run a controlled experiment. Keep all variables the same and change only one. Turn on other lights, blown fuse, broken bulb… -Look at the data and facts. No other lights work; it is storming outside Conclusion: Lightning/wind broke a power line *If no good answers are available go back and find more research and start the process over again. Test / Experiment Draw Conclusion

4. II. Using Scientific Notation A. A way of expressing a number as a value and a power of 10. 1. Why use it??? -easy to use large/small numbers a. 400,000,000  b. 35,300  c. 0.0000456  d. 4.58 x 10 -3  4.0 x 10 8 3.53 x 10 4 4.56 x 10 -5 0.00458

5. Activity (5-7 min) 1. Use a pen/pencil and measure the length of the table you are sitting at. 2. Record your measurement 3. Repeat using a different pen/pencil 4. Record your measurement Think…Why are your measurements different from each other???

6. III. Standards of Measurements A. Standard – an exact quantity that people agree on. 1. Ex: a = 12 inches 2. a mile = 5280 feet

7. IV. Different Systems A. English System – feet, gallons, cups, inches… 1. U.S. only country to use it. B. SI System 1. 1960 by the French 2. Used worldwide 3. Based on powers of 10

8. Common Prefixes (pg. 17) Giga  10 9 1,000,000,000 Mega  10 6 1,000,000 Kilo  10 3 1,000 Hecto  10 2 100 Deka  10 1 10 Base  10 0 1 Deci  10 -1 0.1 Centi  10 -2 0.01 Milli  10 -3 0.001 Micro  10 -6 0.000001 Nano  10 -9 0.000000001

10. Examples 1. Convert 1.0 m to dm?  10 decimeters 2. A road is 1000 m in length. What is this in km?  1 kilometer 3. A small new planet is found 3 light years away from Earth. If the diameter of this planet is 23,500 meters, how many kilometers is its diameter?  23.5 kilometers

11. Assignment 1.2 1. 2.3 millimeters  centimeters 2. 4.05 kilometers  meters 3. 5.7 micrometer  millimeters 4. 10.01 Megameters  kilometers 5. 0.0003 hectometers  millimeters 6. 1,234,567 micrometers  Megameters 7. 1.34 x 10 3 deciliters  liters

12. Answers to previous: 1. 0.23 cm 2. 4050 m 3. 0.0057 mm 4. 10010 km 5. 30 mm 6. 0.000001234567 Mm 7. 134 L

13. SI System Introduction mg Prefix Unit measured milli gram

14. Length A. Def – the distance between 2 points 1. base unit = meter 2. Ex: meter, millimeter, hectometer

15. Volume (derived unit) A. Def. – the amount of space occupied 1. formula: length X width X height a. Must be same units 2. base unit = liter (liquids); meter (solids) a. **1 cm 3 = 1 ml** 3. solids are always cubed (cm 3, m 3 ) 4. is a derived unit

16. Volume Example A liquid is poured into a container. If the dimensions of the container are 45 cm, 54 cm, and 80 cm what is the volume of the liquid in cm 3 ?  194,400 cm 3 The sides of a box are 45 cm, 54 cm, and 0.4 dm. What is the volume of the box in cm 3 ?  9,720 cm 3

17. Mass A. Def. – the amount of matter in an object 1. base unit = gram 2. kilograms is used frequently

18. Density (derived unit) A. Def. – Mass per unit of volume 1. formula: density = mass / volume 2. is a derived unit

19. Density Example What is the density of an unknown metal that has a mass of 178.0 grams and a volume of 20.0 mL? ***Remember D=M/V***  8.9 grams/mL Will this object float in water??? (1.0 g/ml) NO

20. Time and Temperature A. Def. – Time is the interval between two events. 1. Base unit = second B. Def. – Temperature is the amount of heat contained in a substance 1. Base unit = Kelvin/Celsius

21. Temperature Scales a. Celsius Scale – used for most scientific work i. 0 = freezing point of water ii. 100 = boiling point of water iii. 20 = room temperature iv. 37 = body temperature b. Kelvin scale i. 0 on the Kelvin Scale is absolute zero (-273 C.) ii. to convert Celsius to Kelvin add 273 K iii. to convert Kelvin to Celsius subtract 273 K

22. Temperature Example The outside temperature is 29 degrees Celsius. What is it in Kelvin?  302 Kelvin A person has a temperature of 313 Kelvin. Does this person have a fever?  yes; the body temp is 40 deg C.