Post on 18-Jan-2016
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Scientific Method & Graphing Review
1. Problem Statement 2. Observation before Experiment/Research
3. Formulate a Hypothesis4. Experiment5. Observation6. Conclusion
Steps of the Scientific Method
1.1. Problem Statement /QuestionProblem Statement /Question: a) Uses critical thinkingb) Look at facts/Researchc) Looks for patterns
Steps of the Scientific Method
2. Research/Observation before Research/Observation before ExperimentExperiment:
BE OBJECTIVE!
a) Find out factsb) Look for patterns
Steps of the Scientific Method
3. Formulate a HypothesisFormulate a Hypothesis: “an educated guess”
a. Shows a relationship between the independent and dependent variables.
b. Testable predictionc. Explains how/why something works/occurs
Example: If soil temperatures rise, then plant growth will increase.
Steps of the Scientific Method
4. ExperimentExperiment: An organized procedure for testing a
hypothesis.Include a detailed materials list.
Step by step procedure
The procedure has TWO specified “groups”
Before we begin explaining- let’s get our brains ready.
What do these words mean?• Control group• Experimental group• Constant• Dependent variable• Independent variable
Why do you need Constants?
CONSTANTS -you must control any other variables that may
affect your results• Ex- if you are testing a fertilizer, you must keep the
temp, precipitation, acidity of soil, amount of sunlight etc. constant
Experimental group vs. Control Group
• There are two kinds of groups in an experiment– Experimental group:
• The group you are testing• Ex- the plants that receive the fertilizer
– Control group• The group that does not receive the independent
variable• ex.- the plant that do not receive the fertilizer
Control Group• Standard for comparison
– To compare the results of your variable group
• Does NOT contain the Independent VARIABLE – What you are testing
• Contains all the CONSTANTS– What you are keeping the same
• Shows that your results are related to the condition being tested.
• To make sure your results are actually because of your variable
Experimental (Test) Group
The group where you actually test the effect of your variable.
• Contains the experimental variable– Remember: Variables are things that can
CHANGE (vary) in an experiment– There are two variables in every
experiment…
Independent VariableA. The independent, or manipulated
variable, is a factor that’s intentionally varied by the experimenter.
B. Plotted on the X axis of a graphC. “Causes” your results
Dependent Variable A. Depends on (will change because
of) your independent variableB.Plot on the Y axis of a graph
C.Is your results
Example
• If plant growth and fertilizer are related, then when given fertilizer, plants will grow taller.
• What is the INDEPENDENT VARIABLE?– fertilizer
• What is the DEPENDENT VARIABLE?– Plant growth
Hypotheses relate to the variables…
The hypothesis is an educated guess about the cause and effect relationship
between the independent and dependent variables.
-The effect of the INDEPENDENT VARIABLE on the DEPENDENT VARIABLE
Steps of the Scientific Method
5. ObservationObservation:a) Results of the experimentb) Recorded as data tables, charts,
graphsc) Two kinds…
Kinds of dataKinds of data
Quantitative Data: Can be measured. Usually includes a number.
Ex: 6 feet tall, 20 cm long“Quantity”
Qualitative Data: Descriptions that can be observed but not measuredEx: purple, smelly, sharp
“Quality”
Steps of the Scientific Method
6. ConclusionConclusion: contains 3 itemsa) Include a statement that accepts or rejects
the hypothesis.b) Summary of experimental resultsc) Make recommendations for further study
and possible improvements to the procedure.
Tables and Graphs
Tables• Title• Label columns or
rows• Place unit of
measurement in top of column or row
• What’s missing on this table?
Graphs: Visual Display of Data
Do you remember where the independent and dependent variable go? Hint: Remember “IX” center
X Axis: Independent Variable
Y Axis:DependentVariable
Graph Info
• Always need a table first• Title• Label axis along with units of
measurement• Scale on axis must be of equal intervals
(you decide; are you going by 2’s, 5’s, or 10’s etc)
• One exception is the first interval
This graph does NOT start at zero, but each interval is still equal…
Types of graphs
• Bar Graph: Information collected by counting
Line Graph- Shows Trends
• The plotted points or dots represent data
• Circle uncertain values
• Use a best fit line or curve to show the average of data
Interpolate or Extrapolate?
• Interpolate- Estimating data within a set of data points
• Extrapolate- Estimating data beyond a set of data points
Circle (pie) Graph
• Shows how a quantity is broken into parts• Sometimes percentage of a whole