AKA THE SCIENTIFIC METHOD

THE ACQUIREMENT OF SCIENTIFIC KNOWLEDGE

WHAT IS THE SCIENTIFIC METHOD?

•Defined as an organized,

logical approach to

solve a problem or question

STEPS OF THE SCIENTIFIC METHOD

•Define a Problem or Ask a Question• A clear statement of the problem or

question is a crucial step in beginning an investigation

STEPS OF THE SCIENTIFIC METHOD

• Make Observations• Use of all or some of the senses

(sight, taste, feel, hearing, or smell)• Called a qualitative observation

• Make a measurement• Called a quantitative observation

STEPS OF THE SCIENTIFIC METHOD

•Formulate a Hypothesis• Predict a possible answer to the problem

or question• It should be based on facts and

observations• Should be capable of testing

STEPS OF THE SCIENTIFIC METHOD

•Designing and Performing an Experiment• Develop and follow a procedure• Include a detailed materials list

• The outcome must be measurable (quantifiable)• Experiment must be controlled and include

independent and dependent variables!• Experimental evidence will either support or

contradict hypothesis

INDEPENDENT VARIABLE(THE CAUSE)

• The independent, or manipulated variable, is a factor that’s intentionally varied by the experimenter• Goes after the “If” in your hypothesis!

DEPENDENT VARIABLE(THE EFFECT)

• The dependent, or responding variable, is the factor that may change as a result of changes made in the independent variable• Goes after the “Then” in your hypothesis!

CONTROL GROUP• In a scientific experiment, the control is the group that serves as the standard of comparison• The control group may be a “no treatment" or an “experimenter selected” group

CONTROL GROUP• The control group is exposed to the same conditions as the experimental group, except for the variable being tested

All experiments should have a control group!

STEPS OF THE SCIENTIFIC METHOD

• Collect and Analyze Results• Data, such as observations and

measurements, are recorded and then analyzed• Confirm the results by retesting• Put your data into a data table• Make the data table into a graph• Graphs make it easier to see patterns in the data!

• DRY MIX• Dependent variable = Responding variable = Y-axis• Manipulated variable = Independent variable = X-axis

• If the data support the hypothesis, then the conclusion would state that the hypothesis is supported• If the data contradict the hypothesis, then a

new hypothesis must be made and tested

STEPS OF THE SCIENTIFIC METHOD

•Draw a Conclusion• Scientists base their conclusions on

observations made during experimentation• Include a statement that accepts or rejects the

hypothesis• A hypothesis is NEVER correct or incorrect

• Make recommendations for further study and possible improvements to the procedure

IN SUMMARY…

• Careful observation and collection of data is the foundation of any experiment• Observations must be reproducible and may be

categorized as:• Qualitative• Descriptive, e.g., blue

• Quantitative• Measureable, e.g., 4.0 cm

• What is an inference?• An inference is an explanation or assumption of what is

observed• These are conclusions and may change as more data is

collected

TIME FOR THE CANDLE DEMO

• Watch closely and list as many observations as you can on page 14 of your notebook!• Then, identify each observation as quantitative,

qualitative, or an inference

• A table like the one below may be useful in organizing your thoughts:

Observation Qualitative

Quantitative

Inference

WHOA!!

• Did any of your earlier observations change after your last observation (eating the candle)?

• How does this relate to what we discussed about the scientific method?

YOUR TURN!

• Time to apply the scientific method with the Gum Lab!