SCIENTIFIC METHOD

WHAT IS SCIENCE?  IT IS A METHOD OF STUDYING THE NATURAL WORLD

THE SCIENTIFIC METHOD  The scientific method is the only scientific way accepted to back up a theory or idea. This is the method on which all research projects should be based. The Scientific Method is used by researchers to support or disprove a theory.

SEVEN STEPS OF SCIENTIFIC METHOD  1. OBSERVATION  2. ASK A QUESTION  3. HYPOTHESIS  4. EXPERIMENT  5. ANALYZE  6. CONCLUSION  7. TELL IT!!

OH HECK? HOW DO I REMEMBER??? OH HECK O? HEAC OH HECK O?HEAC OH HECK O?HEAC O? HEAC ….. TELL IT

O? HEAC  O --- OBSERVATION  ? ---- QUESTION  H ---- HYPOTHESIS  E EXPERIMENT  A ANALYZE  C CONCLUSION  TELL IT

O? HEAC  O? HEAC tell it

WITH A PARTNER  O? HEAC tell it WRITE IT / PRACTICE WITH A PARTNER NOW

O? HEAC  O --- OBSERVATION  ? ---- QUESTION  H ---- HYPOTHESIS  E EXPERIMENT  A ANALYZE  C CONCLUSION  TELL IT = to other people

OBSERVATION  Observe an event in nature  Gathered through your senses

OBSERVATION….example  An example of an observation might be noticing that many salamanders near a pond have curved, not straight, tails

QUESTION  Wonder why or how it occurs.  Question of WHY? Or HOW? Is the problem.  Ex. Why objects fall to earth?  What causes day or night?  Why does the earth rotate

HYPOTHESIS  A possible explanation for a problem using what we observe  A suggested solution to the problem.  Must be testable  Sometimes written as If…Then… statements  Predicts an outcome

Hypothesis example  An example of a hypothesis might be that the salamanders have curved tails due to a pollutant in the moist soil where they live.

EXPERIMENT  A procedure to test the hypothesis.  Experiment tests the effect of one thing on another using a CONTROL. AND ??? WHAT ARE THEY??  VARIABLES AND CONTROLS??? WHAT ARE THEY??

VARIABLES  Experiment usually contains at least 2 variables.  VARIABLE  VARIABLE – is a quantity that can have more than a single value. (something that can change)  Variables are things that affect your questions. Air, temp, etc.

2 types of variables  DEPENDENT VARIABLE – value changes according to the changes in the other variables.  INDEPENDENT VARIABLE – the variable that is changed to see how it will affect the dependent variable.

Examples of controls and variables  For example, suppose you want to figure out the fastest route to walk home from school.  You will try several different routes and time how long it takes you to get home by each one.  Since you are only interested in finding a route that is fastest for you, you will do the walking yourself

LETS FIGURE THIS OUT  DEPENDENT VARIABLE: this changes because of changes to another variable.  Possible variables would be………  TIME it takes to walk home?  ROUTE you choose to take home?  PERSON who is walking?  In our quest to find a quicker route home……….what changes because something else changes?  TIME.. Dependent variable

LETS FIGURE THIS OUT  INDEPENDENT VARIABLE: What do we change in order to see how the Dependent Variable (TIME) changes?  Possible variables would be………  TIME it takes to walk home?  ROUTE you choose to take home?  PERSON who is walking?  In our quest to find a quicker route home……….what do we change to effect dependent variable?  ROUTE HOME.. Independent variable

LETS FIGURE THIS OUT  CONTROL: this is the variable that does NOT change.  Possible variables would be………  TIME it takes to walk home?  ROUTE you choose to take home?  PERSON who is walking?  In our quest to find a quicker route home……….what remains the same even if we change the Independent and dependent variables?  Person walking.. control variable

What are the variables in your experiment?  Varying the route is the independent variable  The time it takes is the dependent variable  Keeping the same walker throughout makes the walker a control variable.

CONSTANT  CONSTANT – A factor that does not change when other variables are changed

CONTROL  CONTROL – the standard by which the test results can be compared. Controls are NOT being tested. Controls are being used for comparison only

ANALYZE DATE ANALYZE – recording observations and organizing the test data (results) into easy to read tables and graphs. The results of your experiment.

CONCLUSION  The answer to the hypothesis based on the data obtained from the experiment

TELL IT!!!!!!  Share information with others. Write report, Charts, etc.  stop

● The independent variable answers the question "What did I change?". ● The dependent variable answers the question “Because I changed something, what did I observe?".

GRAPHING ● X axis: independent variable ● Y axis: dependant variable  MAKE A HAND to remember which is x and y. X – horizontal Y- vertical

PIE, LINE, BAR, or SCATTER graphs ● Pie graphs are used when percentages are being compared ● Line graphs are used to show change over time ● Bar graphs are used to compare things from different groups or categories ● Scatter plot (we don’t use these too much in science)

● If something directly affects something else, we call it directly related (positive correlation) ● Example: When x goes up, y goes up ● Inversely proportionate (negative correlation) is when the opposite of both happens ● Example: When x goes up, y goes down

 Inversely proportionate Directly proportionate

SCIENTIFIC THEORY ● If many experiments by different scientists support a particular hypothesis, becomes scientific theory- an idea, principle, or model that usually ties together and explains many facts that previously appeared to be unrelated and is supported by a great deal of evidence.

SCIENTIFIC LAW  Scientific law- a description of what we find happening in nature over and over in the same way, without known exception. (ex: Newton’s Law)

SO WHAT IS THE DIFFERENCE ● Law- tells you WHAT is going to happen, because it’s happened before ● Law of Gravity ● Theory- explains WHY it is happening ● Theory of Continental Drift ● YES- lots of them are ● Consider this: Can a theory be factual? ● Sometimes theories seem like laws

LAW OR THEORY?????? ● If I drop an apple, it will fall ● Law ● Newton says that gravity is why the apple falls to the ground ● Theory ● Protons and Neutrons are located inside of the nucleus ● Law ● Dalton says chemical reactions occur because of the rearrangement of atoms ● Theory (Atomic Theory…)

OBSERVATION / Inference  OBSERVATION - Use one or more of the 5 senses to gather information.  Record facts!  Observation is what you see!  INFERENCE – is using the observed facts to come up with WHAT YOU THINK HAPPENED or CAUSED.  If your inference is TESTABLE….. YOU NOW HAVE A HYPOTHESIS!!!!!