Annie Benedict 2015 The Scientific Method Annie Benedict

Annie Benedict, 2015 The Scientific Method

Annie Benedict, 2015 Scientific Method – what is it? �Dictionary. com: a method of research in which a problem is identified, relevant data are gathered, a hypothesis is formulated from these data, and the hypothesis is empirically tested.

Annie Benedict, 2015 Scientific Method – what is it? �In simple terms: �Going through a step-by-step process to test a scientific hypothesis �…and then you tell people about it afterwards!

Annie Benedict, 2015 Ask a question �A scientific question must be: �Specific �Concise �Testable

Annie Benedict, 2015 Ask a question �“Where do birds like to live? ” �NOT SPECIFIC, so not testable �“Do northern cardinals nest in the lower branches or upper tree canopy in Longfellow Park? ”

Annie Benedict, 2015 Ask a question �Can magnets defy gravity? �…nothing defies gravity…? Not testable �Not specific �Does the distance of a conductive metal (copper) surrounding a magnet affect the speed it falls?

Annie Benedict, 2015 Do background research �Stay focused! �Detailed information is nice, but you want to research relevant topics �Has anyone else studied your topic before? �Ex: Mating calls of the eastern bluebird are nice to know, but not relevant

Annie Benedict, 2015 Do background research �Eddy currents are circular currents caused when a magnet reacts with a conductor �Conductor: metals such as copper �When a magnet reacts with a conductor, the magnetic field induces an eddy current within the conductor. �The induced eddy current produces a magnetic field. �This magnetic field opposes the one of the falling magnet, so the magnet slows down. If the opposing magnetic field is strong enough, the magnet will levitate within the tube. �Similar experiments: http: //www. sciencebuddies. org and www. coolmagnetman. com/magpipes. htm

Annie Benedict, 2015 Construct a hypothesis �What is a hypothesis? �If ____, then _____ because _____. �Prediction vs. hypothesis?

Annie Benedict, 2015 Prediction vs. Hypothesis? �Prediction: �Male betta fish will react aggressively to other male betta fish. Hypothesis: If a male betta fish is placed into a tank with a second male betta fish, then both fish will react aggressively to each other because male betta fish compete for mates.

Annie Benedict, 2015 Construct a hypothesis If a magnet is dropped down copper pipes of different diameters, then the magnet will fall slowest through the pipe with the smallest diameter because the walls of the pipe are closest to the magnet and so will produce a stronger magnetic field and a greater resistance.

Annie Benedict, 2015 Design an experiment �Tests the question, based upon the hypothesis �Experimental design will be occurring throughout the prior 3 steps as well! �(And may occur afterwards, too)

Annie Benedict, 2015 Parts of an experiment �Variables! �Independent variable �What you are changing – the cause �Aka “manipulated variable” �Ex: type of liquid fed to plant �Dependent variable �What happens because of the thing you change – the effect �Aka “responding variable” �Ex: plant growth

Annie Benedict, 2015 Parts of an experiment �Controlled variables �Aka “constants” or “experimental constants” �Things you keep the same �Ex: type of plant, pot size, location in sun, volume of liquid added, etc

Annie Benedict, 2015 Parts of an experiment �Experimental groups �Groups where everything is same EXCEPT the independent variable �Ex: plant fed orange juice, plant fed Diet Coke, plant fed milk �Control group �The neutral group, to compare to the experimental groups �The “norm” �Ex: plant fed water

Annie Benedict, 2015 Parts of an experiment �Replicates/Trials �Every test must have replicates! �Why? � To ensure scientific data is correct and accurate; not a fluke �The higher the number of trials, the more reliable your results.

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Annie Benedict, 2015 Design an experiment �Set up three 61 cm (2 ft) copper pipes of different diameters – 1. 27 cm (½ in. ), 1. 91 cm (¾ in. ), & 2. 54 cm (1 in. ). �Set up three PVC pipes of the same diameters as the control. �Drop a cylindrical neodymium magnet down the center of each pipe and record the time it takes to reach the bottom with a stopwatch. �Conduct each experiment ten times.

Annie Benedict, 2015 Design an experiment

Annie Benedict, 2015 Subjective vs. objective data �Objective – observations, objects. Uses measurements. �Ex: 3 inch growth, 4 leaves wilted, 6 seconds to pass through pipe, nest 2 feet in diameter. �Subjective – based on opinion. �Ex: plant looked good, leaves looked nasty, short time, nest was big. NOT SCIENTIFIC!

Annie Benedict, 2015 Test the experiment �Data must be objective �Also take visual observations as notes (can be subjective) �Collect the objective data in a table

Annie Benedict, 2015 What is a data table?

Annie Benedict, 2015 Procedure working? �If it doesn’t work – figure out what’s going wrong, then go back and retest �If it’s working – can move on

Annie Benedict, 2015 Analyze data �What is analyzing? �Examining the data to understand its patterns and why it happens

Annie Benedict, 2015 Analyze data �Scientists analyze data using graphs. �Different graph types are used for different purposes.

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Annie Benedict, 2015 Draw conclusions �Do your data support or not support your hypothesis? �What does the analysis of your data tell you about your topic?

Annie Benedict, 2015 Communicate Results �Why do scientists communicate their results?