2Scientists use experiments to test a hypothesis or answer a question
3Variables are factors or parts that can change during an experiment What is a Variable?Variables are factors or parts that can change during an experiment
4Manipulated (independent) variable: what you change on purpose What is a Variable?Manipulated (independent) variable:what you change on purposeThere is only ONE MV in an experiment
5Responding (dependent) variable: What you are measuring. What is a Variable?Responding (dependent) variable:What you are measuring.
6Controlled variables: What you keep the same (also called constants.) What is a Variable?Controlled variables:What you keep the same (also called constants.)
7Parts of an Experiment QUESTION/PROBLEM What question is being answered, problem solved, or hypothesis tested. What is the purpose of doing the experiment?What is the effect of MV on RV?How does MV affect RV?
8Parts of an Experiment Hypothesis An educated guess or a prediction about the results.If (the manipulated variable does this),then (the responding variable) will (describe what will happen)because (give a reason for your prediction)
9Parts of an Experiment Materials: Items used during the experiment. Write in a bulleted list.Include details – how much you will need, units of measurement, sizes
10Parts of an Experiment Procedures: Steps followed during experiment. Write in a numbered listShould be detailed enough that anyone can follow exactly what you did.Always say to “Record Data”Always say how many times the experiment will be repeated (4 total trials)
11Parts of an Experiment Observations/Data: All the information gathered whileperforming the experiment.Should include written observations AND a data table
12Parts of an Experiment Results/Conclusions: Analyze your data to determine the final outcome of the experiment. What do you NOW believe as a result of the experiment or observations?
13Parts of an Experiment Results/Conclusions: 1. Make a Graph Decide on the kind of graph: Time progression = line, Objects = barSet up your axis rangeLabel your axes (x=MV, y=RV)Title your graph
14Parts of an Experiment Results/Conclusions: 2. Write a conclusion paragraphRestate your hypothesis and relate your findings to it (correct or incorrect)Support your claim with at least 2 pieces of data – use numbers from your data table!Explain why/how your data supports your answer
15Parts of an Experiment Share your results: Publish your findings so that others may benefit from your work.
16Observations & Inferences Description of objects, eventsMay include data from all five senses (touch/texture, smell, taste, sight, sound)Could be drawings, diagrams, written wordsDo not include opinions.
17Observations & Inferences Drawing conclusions based on observationsOften provide a reason for the event/object being observed.
18Scientific Method Page (Joe & The Birthday Cake) ExampleScientific Method Page(Joe & The Birthday Cake)
19THeories & LawsLay people often misinterpret the language used by scientists. And for that reason, they sometimes draw the wrong conclusions as to what the scientific terms mean. Three such terms that are often used interchangeably are "scientific law," "hypothesis," and "theory."In layman’s terms, if something is said to be “just a theory,” it usually means that it is a mere guess, or is unproved. It might even lack credibility. But in scientific terms, a theory implies that something has been proven and is generally accepted as being true.
20More like a scientific law than a hypothesis. THeoriesMore like a scientific law than a hypothesis.Explanation of a set of related observations or events based upon proven hypotheses.Verified multiple times by detached groups of researchers.One scientist cannot create a theory, he/she can only create a hypothesis.Examples: The theory of evolution, the theory of relativity, and the quantum theory.
21Examples: The law of gravity, the law of thermodynamics. lawsA statement of fact meant to explain, in concise terms, an action or set of actions.Generally accepted to be true and universal, and can sometimes be expressed in terms of a single mathematical equation. Scientific laws are similar to mathematical postulates. They don’t really need any complex external proofs; they are accepted at face value based upon the fact that they have always been observed to be true.Examples: The law of gravity,the law of thermodynamics.
22Both are used to make predictions of events. similaritiesBoth a scientific theory and a scientific law are accepted to be true by the scientific community as a whole.Both are used to make predictions of events.Both are used to advance technology.
23A theory is much more complex and dynamic. DifferencesA theory is much more complex and dynamic.A law governs a single action, whereas a theory explains a whole series of related phenomena.
24An analogy can be made using a slingshot and an automobile. Theories & LawsAn analogy can be made using a slingshot and an automobile.A scientific law is like a slingshot. A slingshot has but one moving part--the rubber band. If you put a rock in it and draw it back, the rock will fly out at a predictable speed, depending upon the distance the band is drawn back.
25Theories & LawsAn automobile has many moving parts, all working in unison to perform the chore of transporting someone from one point to another point. An automobile is a complex piece of machinery. Sometimes, improvements are made to one or more component parts. A new set of spark plugs that are composed of a better alloy that can withstand heat better, for example, might replace the existing set. But the function of the automobile as a whole remains unchanged.
26Theories & LawsA theory is like the automobile. Components of it can be changed or improved upon, without changing the overall truth of the theory as a whole.
27Excerpted from http://wilstar.net/science/ Theories & LawsExcerpted from