Topic: Investigation and the Scientific Method

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Topic: Scientific Method

What is the scientific method?

Individual work (Classwork):

Write down the detailed steps to make a peanut butter and jelly sandwich

The Scientific Method

Observation

Hypothesis:

Educated Guess

Experiments

Materials

Method

Results:

Must be Measurable

Conclusion:

Ideas about results

The Scientific Method

Observation/ State the Question or Problem

Hypothesis - Educated idea

Experiment – Repeatable test

•Materials

•Method

Results - Measurable Data – Number/ Countable

Conclusion - Ideas about the results, comparison

Accept or Adjust Hypothesis

Observation.

Some lab people will say this step is to

State the Problem, but that is because they have already observed the way it should go.

Newton – apple on head?

Galileo – wandering stars

Hypothesis

• an Educated Idea (or prediction), not guess . Guesses are random, and based on the observations scientists have an idea

(right or wrong) about how they think nature works.

All students can achieve

Experiment

Repeatable Test –. If another scientist can’t redo your experiment or your results, they are a miracle (religion not science).

Cold fusion (Russia)

Human cloning (North Korea)

Results

• Data– Numbers or values. Numbers by themselves mean nothing. Numbers lie. They can be manipulated or misinterpreted.

In the 2004 Presidential election both candidates said they would win based on the same numbers, and both were right and wrong. One won the popular vote, the other the Presidency.

Conclusion

• How did the results work based on the hypothesis. Did we support or disprove our idea.

• One of the most common mistakes is to draw a conclusion that has nothing to do with your hypothesis- for example to talk about desert animals after doing research on animals living in a swamp.

Extrapolation – extending results far beyond experiment, talking about the Nile, after researching the Colorado

Hypothesis - Educated Idea

If your conclusion is that your hypothesis is supported you may have discovered an idea that shows how nature works. If it can be expanded to fit all of the ideas in that category

(say physics or chemistry or biology) than it has a specific name.

THEORY.

Theory - Cumulative Evidence of corrected hypotheses

A theory is one of the most misused words in the

American English vocabulary. In science it is very specific- A large idea

SUPPORTED by many experiments, that is true almost all of the time

(99%). Theories have some flaw, like being unable to show how the original cell developed (Cell theory).

Law - Happens every time

IF a theory were true all the time in science it would be the ultimate idea- a LAW.

A LAW, like gravity, is always true. If it is disproved then it must be reworked to account for the change. Even Einstein’s ideas underwent changes as we discovered new things.

Things I DO NOT say in my class (except sarcastically)

THE TRUTH. NO such thing in science. Everything is up to question as long as done in the proper way-using the SCIENTIFIC METHOD.

Just saying you don’t believe it is not enough. You have to disprove it in a repeatable way.

Disprove Idea

Support Idea

PROOF. The other forbidden word. A real scientist would not use this word at a scientific convention. We have evidence, support, confirmation, verification, data, substantiation or indications that this is how nature works but never PROOF.

DO all scientists use the same scientific method?

• No

• Each has a unique perspective, but generally the same formula

• Visit my website and look up two different sites, and compare and contrast their scientific method

Individual work (Classwork): Write down the detailed steps to make a peanut butter and jelly sandwich

Scientific Methods

Observation

Question a reasonable answer to the question

Hypothesis

Experiment result agrees with hypothesis valid

Conclusion result does not agree with hypothesis invalid

1.Observation

2.Question

If the result does not support hypothesis

4.Experiment

3.Hypothesis

5.Conclusion

Scientific Methods

Observation

1. Suffer either smallpox or cowpox once in a lifetime 2. Milk maids who had suffered from cowpox never had smallpox

Question

Why do milk maids suffer from cowpox never suffer smallpox?

Hypothesis

A patient after recovering from cowpox will become resistant to both cowpox & smallpox germs

Experiment valid

Conclusion invalid

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