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## Chapter One

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**Chapter One**Science Skills**Daily Assignment**• What is Science? Where does it come from?**What is Science**• Science begins with curiosity and ends with discovery. • Science can also happen by accident. • Science versus Technology • Science aims to understand the world • Technology aims to change the world**Branches of Natural Science**• Physical Science • Chemistry and Physics • Earth and Space Science • Geology and Astronomy • Life Science • Biology**Physical Science**• Space and Time • Matter and Change • Forces and Motion • Energy**The Scientific Method**• The Scientific Method is the process by which scientists approach the solving of a problem. • Sometimes scientists make discoveries by accident, but many are solved in this manner.**Identify the Problem**• Present the problem in a question form. Examples: • Which paper towel is the most absorbent? • Which cell phone gives the most bars in our area?**Gather information**• Use observations to gain perspective and data about your problem.**Hypothesis**• Make a testable solution to the problem. • Base your hypothesis on the information you’ve collected**Design an Experiment**• Plan an experiment to test the hypothesis. • This should be performed under controlled conditions.**Perform the Experiment**• Follow your plan as written. Collect data and note any problems with your procedure.**Analyze the data**• Use the information collected to support or refute your hypothesis • Make a choice Hypothesis not supported by data Data supports my hypothesis**Conclusion**• Communicate your results. • Make charts and/or graphs to summarize your results. • If your hypothesis is wrong, come up with a new one!**The Variables**• Independent Variable: is the item which you will change in the experiment. • Dependent Variable: is the item that will change depending on what independent variable is used. • Control: the experiment run changing only one variable at a time.**Example Experiment**• Suppose my electricity bill was higher than normal recently (Problem). • I would notice that my bills have been getting higher recently (Gathering Data) • I believe that this is caused by my old refrigerator (Hypothesis)**Example Experiment**• I plan to test all of my appliances using an Ohm meter to see which draws the most electricity (Designing the Experiment) • I test all of my appliances to see which draws the most current (Perform the Experiment) • I then analyze the data and notice that my refrigerator does draw the most power, but it has not been running more than usual. (Conclusion?)**Example Experiment**• My hypothesis was wrong, so I need to get a new one! • Perhaps something has been used more frequently recently? • It turns out that my ceramic heater was the culprit because it has been working overtime to keep up with the very low temperatures!!**Can you put the Scientific Method to the test ?**Over this weekend, you are to perform an experiment Come up with a question that you want answered Go through the scientific method step by step and try to get an answer.**Can you put the Scientific Method to the test ?**• Come in on Monday either with an answer or a new hypothesis. • Make sure you have all the steps represented of what you did. • This does not have to be a lengthy report, just an explanation.**Theories vs. Laws**• What’s the difference? • A Scientific Law describes a pattern in nature without explaining it. A theory is the accepted explanation of that pattern. • Examples:**Lab Procedures**• Any time we are in a lab setting, the following rules must apply • Do not touch, take, taste, handle, caress, or drink anything without my permission • We may have dangerous chemicals, sharp objects, or other lethal / poisonous materials in the classroom • Make sure your work area is clean before and after the lab**Lab Procedures**• Labs will be most likely accompanied by a lab report, so make sure you are paying close attention to what you are doing. • Always follow my directions exactly. • There is to be no horse play during labs. • All materials and tools are to be returned to me at the end of the lab in their original condition.**Scientific Notation**• A short-hand way of writing large numbers without writing all of the zeros. • The number is written as a base X power of 10. • 2.3 x 10 5**The Distance From the Sun to the Earth**• 93,000,000 miles**Step 1**Move decimal left Leave only one number to the left of decimal 93,000,000 .= 9.3000000**Step 2**Write number without zeros 93,000,000 = 9.3**Step 3**Count how many places you moved decimal Make that your power of ten 7 93,000,000 = 9.3 x 10**98,500,000 =**64,100,000,000 = 279,000,000 = 4,200,000 = 9.85 x 107 6.41 x 1010 2.79 x 108 4.2 x 106 Practice Problem Write in scientific notation. Decide the power of ten.**What about really small numbers?**Picture of a dust mite on the top of a pinhead The size of dust mite is 0.00000000024 meters**For numbers less than zero**• Move the decimal right, so there is one numeral to the left of the decimal. 0.00000000024 = 2.4 • Count the number of spaces you moved the decimal. This becomes the exponent. The exponent is negative. 2.4 X 10 -10**More Practice Problems**734,000,000 = _____________ 870,000,000,000 = __________ 90,000,000,000 = ___________ 0.0000000034500 = _________ 0.0000122 = ______________ 0.00454000 = _____________ On these, decide where the decimal will be moved.**Scientific Notation to Standard Form**When the exponent is positive, move the decimal to the right 3.4 x 105 in scientific notation 3.40000 --- move the decimal 340,000 in standard form**6,270,000**90,100 Write in Standard Form Move the decimal to the right. • 6.27 x 106 • 9.01 x 104**When the exponent is negative, move the decimal to the left.**Add zero’s as spacers. Scientific Notation to Standard Form • 4.33 x 10-6 in scientific notation • 0.00000433 --- move the decimal left**Write in Standard Form**7.11 x 10-4 5.001 x 10-8 2.34 x 10-20 0.000711 0.00000005001 0.0000000000000000000234 Move the decimal to the left.**Introduction to the Metric System**Click here**Daily Assignment**• Multiply (no calculators) the following: 3 X 5 = a x 2 = 2 4 3 4ac**A History of Measurement**In all traditional measuring systems, short distance units were based on the dimensions of the human body.**A History of Measurement**Historical = current = measurement Uncia = Inch = width of the thumb Cubit = Foot = length of a foot (length of forearm) Span = Yard = length of arm from nose to finger**Standard Of Measurement**An exact quantity that people agree to use for comparison. Two criteria a standard must meet: Accessible to all Never changing**The English System**Uses historical units based on an agreed upon standard. 1 foot = 12 inches 1 yard = 3 feet The English system is used primarily in the USA only.**Length**Is defined as the distance between two points Length is measured using aRuler English units of length are inch, foot, yard, and mile.**Mass**Is defined as the amount of matter in an object. Is measured using aBalance English units are ounces, pounds, tons**Volume**Is the amount of space an object takes up Volume - solid Liquid volume**Volume (continued)**Liquid English units are ounce, pint, quart, gallon Solid English units are pint, quart bushel, peck,**Time**Is defined as the interval between two events Is measured using a stopwatch or a clock**Temperature**Is defined as the amount of energy contained in an object Is measured using aThermometer**Daily Assignment**Estimate your age as a decimal Ex : Birthday June 1st = 15.5 years Birthday Feb. 5th = 15.1 years Now, convert your age in years to your age in seconds.