the scientific method a way to solve a problem. what is the scientific method? it is the steps...
TRANSCRIPT
The The Scientific Scientific MethodMethod
A Way to Solve a A Way to Solve a ProblemProblem
The The Scientific Scientific MethodMethod
A Way to Solve a A Way to Solve a ProblemProblem
What is the Scientific Method?
• It is the steps someone takes to identify a question, develop a hypothesis, design and carry out steps or procedures to test the hypothesis, and document observations and findings to share with someone else.
• In other words, it’s a way to solve a problem.
The steps of the Scientific Method are:
• State the problem• Gather Information• Form a Hypothesis• Test the Hypothesis• Record and Analyze
Data• State the Conclusion• Repeat the Work
Mnemonic sentence• Forming a sentence by using the
first letter from a list of terms in assisting or intended to assist memory
Mnemonic sentence
Scientist have to take the time to think logically when they are investigating a question or problem.
• They break things down into many steps that make sense.
Scientists develop a question, gather information and form a hypothesis.
What is a Hypothesis?1. A Hypothesis is a
possible answer to a question
2. A Hypothesis is a proposed solution to the problem.
3. A Hypothesis is your best guess based on research.
4. A Hypothesis must be testable.
Forming a Hypothesis• A Hypothesis is based
upon information and observations that can be tested. Hypothesis are often stated as if-and-then statements. A hypothesis needs to be testable.
• A Hypothesis can be proven false, but can never be proven absolutely true. This allows other people the ability to verify the results, and leaves the chance to find better explanations as our understanding grows.
If plants are fertilized, then they will grow taller
The next step scientists take is to
create and conduct an experiment to test their hypothesis.
Testing the Hypothesis
• In order to test a hypothesis, you must perform an experiment.
• In any experiment, it is important to keep everything the same except for the item you are testing.
• Two groups are usually tested.
Experimental & Controlled Group
• The Experimental group gets the item that is being tested. The test group.
• Test only ONE condition at a time, everything else same as control.
• The Controlled group – used as a standard for comparison.
• Gets everything that the experimental group received except the tested item.
• All controlled experiments must have a control.
Controlled group
Experimental group
Independent Variable• What the investigator
manipulates, the particular treatment or condition the investigator is most interested in the effects of.
• The item that is being tested.
• The independent variable will always be in the experimental group The effects of steroids
Dependent Variable (Data)• What is measured or
observed, the “data” collected in the experiment.
• Any changes in this variable depend on the change made to the independent variable.
• There are two types of data:
1.Quantitative- of, relating to, or involving the measurement of quantity or amount, (can be expressed as a number)
2.Qualitative- relating to or involving comparisons based on qualities (descriptive)
Dependent Variable (Data)• In the steroid
experiment 25 rats were given anabolic steroids and 25 were given a placebo, the number of aggressive encounters were recorded for each group.
• What are the: control and experimental group. The independent and dependent variables
(steroids) No Drug(placebo)
Dependent Variable
Independent Variable
Steroids
Aggressive Behavior
A key to experiments is observing what happens and writing it down.
• Gathering information or data and documenting it so it is readable and makes sense to others is really important.
Record and Analyzing Data in Experiments
• Collect Data.• Choose a graph
or chart that best fits your experiment.
• Graph may be a bar graph, line graph or pie chart.
Purpose of Using Graphs or Chart
• To show and compare changes.
• To show and compare relationships.
• To Bring facts to life
Advantages of Using graphs• Quick way for the
audience to visualize what you are saying.
• Emphasizes main point.
• Proves a point, they can see and hear it.
• More interesting than just talk or print.
Disadvantages• Time consuming to
make. (Not true if you use technology available now)
• Technical ( audience knowledge to interpret or understand).
• Costly- depending on the medium used (poster board, transfer letters, color prints, size, etc).
A Bar Graph• Called a Histogram.• Numerical dimensions are
shown in bars or varying lengths.
• Shows comparisons.• Multiple comparisons are
possible.• Two items being
compared do not need to affect each other.
• A fast way to show big differences.
A Line Graph• Line graphs can be
used to show how something changes over time
• Shows the relationship between two variables .
• Shows the effect of an independent variable on the dependent variable.
• Shows how things rise and fall in a line graph
Understanding Axis on a line graph
• The variables being compared go on two axis of the graph.
• The independent variable always goes on the horizontal axis, called the x-axis.
• The dependent variable always goes on the vertical axis, the y-axis.
X Axis vs Y Axis
• Usually, the x-axis has numbers for the time period
• y-axis has numbers for what is being measured.
.
Labeling Axis & Recording Data
A Pie Chart• Shows percentages effectively.• Shows how a part relates to the
whole.• Easy to grasp.• Label larger portions in the circle,
smaller outside with leader lines.
Once a scientist completes an experiment, they often repeat it to see if they get the same findings and results.
• This is really what we call verification, or checking things out to make sure everything was valid and will happen again and again.
Scientists share their experiments and findings with others.
• Because they share their experiments and findings, scientists can learn from each other and often use someone else’s experiences to help them with what they are studying or doing.
Creating Graphs• Use the data on each trial from the
number of pill bugs and construct a line graph.
• Use the data on the total number of pill bugs and construct a bar graph.
• Use the data on the average number of pill bugs and construct a pie chart.