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Scientific Inquiry & Problem Solving. Kimberly Davis Dothan High School. Bell-ringer Activity. Quietly p ick up one of each of the handouts from the bookcase. Find your student # on the class roster on the bulletin board at the front of the class.
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Scientific Inquiry & Problem Solving Kimberly Davis Dothan High School
Bell-ringer Activity • Quietly pick up one of each of the handouts from the bookcase. • Find your student # on the class roster on the bulletin board at the front of the class. • Have a seat in the desk that has the same # on it. • Complete the Student Information Sheet.
Agenda • Introduction • Classroom Policies and Procedures • Safety Handout • Tiger Tip Review • Code of Conduct Review • Begin Notes
Essential Question • Why do crime scene investigators use a specific order of steps when investigating a murder?
Discuss • How does a CSI approach a crime scene? • How do they solve the crime?
Experiments/Problem Solving • Something as simple as changing from one type of shampoo to another in hopes of an improved effect is a type of simple experiment. • Can you think of another example?
Cultural Diversity Shamans • Healers • Rainforest of Central & S. America • Observe & test local plants until they find which ones work • Today scientists work with these shamans in manufacturing prescription drugs.
Vocabulary Mixer • In your groups, try to match the vocabulary words with the appropriate definition. • Do not bend the slips of paper! • After I have checked your matches, please put the papers back in the bags and give them to me.
State the Problem • Observations: the information gathered using any of your senses • made throughout the scientific experiment, not only at the beginning • lead you to ask a question or identify (state) a problem
Gather Information • use reference materials such as: • Encyclopedias • Dictionaries • Scientific magazines and journals • World wide web • not all information is relevant or useful to a particular science topic
How do you know if it is relevant? • Is the information outdated? • Is it accurate or just someone’s opinion? Can the information be verified elsewhere? • Is it from a reputable source? • Who is the intended audience? • Why is this the best source to use? • How can the information be used?
Form a Hypothesis • Hypothesis: a possible answer to the question • can be tested by an experiment
Test the Hypothesis • Experiment: tests the affect of one thing on another using controlled conditions • Contain many variables • Variables: the factors that affect the experiment
Variables • Independent variable: the variable that is being tested and is intentionally changed or manipulated • Dependent variable: the variable that might be affected as a result of that intentional change • Constant: factor that does not change when other variables change; • may have numerous constants in an experiment • Control: the standard by which the test results can be compared
Odds tell the Evens: What is the difference between independent and dependentvariables?
Evens tell the Odds: What is the difference between a control and a constant?
How might NASA scientists set up an experiment to solve the problem of the damaged tiles that caused the Columbia space shuttle accident? They might make tiles of many different materials and subject them all to the heat and other stresses encountered by the shuttle.
NASA experiment variables: Independent variable: the materials used Dependent variable: the amount of heat the tile can withstand without being damaged Constants: the conditions to which the tiles were subjected Controls: tiles from the first shuttles
Bird Feeder Experiment • My neighbor has a clear bird feeder that 3 birds frequent each day. • I bought one clear, one red, and one blue feeder to see if color will affect which feeder a bird chooses. • I put the feeders in my yard, each with the same amount and type of food hanging in the same area for the same amount of time.
What are the variables? • Independent variable: the color of the feeder • Dependent variable: which bird feeder is frequented the most or that all are equally chosen, whichever result is true • Constant: amount and type of food, amount of time • Control: the clear feeder
Odds tell the Evens • What is the difference between a constant and a control?
Evens tell the Odds • What is the difference between a dependent and an independent variable?
Gather Information • Gather and record the data in a lab report or chart during the experiment. • Quantitative: involve measurements or numbers • Qualitative: does not involve numbers or measurements
Quantitative Measurement • SI (metric) system:universally accepted standard of measurement • Standard: an exact quantity people agree to use for comparison (ex. meter, gram, liter)
Essential Question: Why have standards of measurement? • to reproduce someone else’s results • Ex. If I say the door is three arm lengths across, what happens when you measure a table to fit through the door with your arm?
Activity Have someone very tall and someone very short walk fifteen steps heel to toe. • Why is there a difference in the distance that they walked? • Are human feet a good method (standard) of measurement? Why or why not?
Common Measurement Units Length/distance: meter (m) Mass: *gram (g) *SI unit mass: kilogram (kg) Volume: liter (l) Time: second (s) Temperature: *degree Celsius(˚C) *SI unit temp.: Kelvin (K) (most common base units used)
Measuring Temperature • Freezing pointof water= 0˚C • Boiling pointof water= 100 ˚C • Human body temp = ≈ 37 ˚C • Room temp= ≈ 20 - 25 ˚C • Coldest possible temp or Absolute zero= 0 K (-273 ˚C) • To convert °Celsius to Kelvin, just add 273 to the Celsius temperature.
Common Base Unit Prefixes kilo- k 1,000 hecto- h 100 deka- da 10 deci- d 0.1 centi- c 0.01 milli- m 0.001 micro- μ 0.000 001
Metric Conversions Remember: King Henry died drinking chocolate milk. For each move right = multiply by 10 -----------------------> khda (base unit) dcm <----------------------- For each move left = divide by 10
Why is it important to know how to convert measurements? • Data can be collected using a variety of tools. (Meter sticks, balances, stopwatches, etc.) • You need to be able to compare your results to a standard.
Practice Problems Convert the following measurements: • 100 cm to __ m • 85 km to __ m • 365 kl to __ ml • 4,050 g to __ kg • 50 cg to __ mg
Answers to Problems • 100 cm = 1 m • 85 km = 85,000 m • 365 kl = 365,000,000 ml • 4,050 g = 4.050 kg • 50 cg = 500 mg
More Practice Problems Convert the following measurements: • 1 l to ____ dl • 400 cm to ____ km • 35,007 km to ____ mm • 1992 kg to ____ cg • 4,875,016 mm to ____ dam
Answers to More Practice Problems • 1 l = 10 dl • 400 cm = 0.004 km • 35,007 km = 35,007,000,000 mm • 1992 kg = 199,200,000 cg • 4,875,016 mm = 487.5016 dam
Measurement Conversion Quiz • 56,000 ml to _____ kl • 0.39 hg to _____ cg • 100 dam to _____ m • 41 mm to _____ m • 1,560 dg to _____ kg
Quiz Answers • 0.056 kl • 3,900 cg • 1,000 m • 0.041 m • 0.156 kg
Is one measurement enough? • No, scientists make repeated measurements to increase the validity and reliability of the results. • This data is then organized into a data table so that others can understand it.
Accuracy: exact, how close you are to the mark (ex. in darts when you hit the bulls eye) • Precision: how often you can hit the same spot (ex. in darts when you hit the 10 point circle three times in a row)
Practice Problem • A student obtained these data after measuring the mass of an object three different times. • 1st measurement: 6.293 g • 2nd measurement: 6.294 g • 3rd measurement: 6.295 g • If object’s mass is actually 5.550 g, these data are best described as — • precise but not accurate
Analyze the Data • Graph: an effective method of organization which helps to understand and communicate data • Bar Graph: measures things that are counted • Line Graph: compares the independent and dependent variables • Circle Graph: measures parts of a whole or percentages
Graph Reading Tips • Carefully read the title and the label on each axis. • Check for any other information that might be included on the graph. • When you think you have the answer, double check the information given in the graph. • Remember: independent variable= on the x-axis dependent variable = on the y-axis
Model: a representation of an actual object or idea that explains the results or how something works or looks • Technology: the application of science to help people • It aids scientists in developing theories and laws.
Draw Conclusions • Conclusions: explanations based on scientific data and observations. • answer the question as to whether or not the data and observations support the hypothesis • may indicate that more information is needed which creates more questions to investigate
Inference: an explanation of the data based on facts but not on direct observation. An inference is like an assumption. • Ex. Your friend has a busted lip, so you infer (assume) that he must have been in a fight. • An observation would be if you actually saw the fight.
Odds tell the Evens: What is the difference between an inference and a observation?
Why are results that do not support the hypothesis important? • help scientists adjust and restate hypotheses • help you to understand the world • sometimes explanations must be modified as new information is learned • Ex. People used to think the world was flat.