a scientific method how science is done. science is a method for answering theoretical questions
TRANSCRIPT
A Scientific Method
How Science is Done
Science
• is a method for answering theoretical questions.
Science
• is a method for answering theoretical questions.
• deals with discovering facts and relationships between observable phenomena in nature.
Science
• is a method for answering theoretical questions.
• deals with discovering facts and relationships between observable phenomena in nature.
• deals with establishing theories that organize and make sense of these facts and relationships.
Technology is different than Science
• Science answers theoretical questions but technology solves practical problems.
Technology is different than Science
• Science answers theoretical questions but technology solves practical problems.
• Science uses technology to answer these theoretical questions.
Technology is different than Science
• Science answers theoretical questions but technology solves practical problems.
• Science uses technology to answer these theoretical questions.
• Technology can be improved or invented through the discoveries made in science. Some technology has even been invented to help do science.
Scientific Facts
• Facts are close agreements between many competent observers about a series of observations made.
Scientific Facts
• Facts are close agreements between many competent observers about a series of observations made.
• It is a fact that the Earth revolves around the Sun.
Scientific Facts
• Facts are close agreements between many competent observers about a series of observations made.
• It is a fact that the Earth revolves around the Sun.
• It is a fact that heavy objects and light objects fall at the same rate in the absence of air resistance.
Scientific Facts
MUST BE CHANGED AS NEW
OBSERVATIONS ARE MADE !!!
Scientific Hypothesis
• An explanation which has yet to be verified by a scientific experiment or observation.
Scientific Hypothesis
• An educated guess which has yet to be verified by a scientific experiment or observation.
• Can be found to be correct, incorrect or inconclusive.
Scientific Hypothesis
• An educated guess which has yet to be verified by a scientific experiment or observation.
• Can be found to be correct, incorrect or inconclusive.
• There must be a test for proving a scientific hypothesis …….
Scientific Hypothesis
• An educated guess which has yet to be verified by a scientific experiment or observation.
• Can be found to be correct, incorrect or inconclusive.
• There must be a test for proving a scientific
hypothesis wrong.
Is this a good scientific hypothesis ?
USC is the best college football team to ever play .
Is this a good scientific hypothesis ?
USC is the best college football team to ever play .
NO !!!!!!!There is no test for wrongness, it is just an opinion.
Is this a good scientific hypothesis ?
USC is the best college football team to ever play .
NO !!!!!!!There is no test for wrongness, it is just an opinion.
If it had said that a majority of people think this, then this could be proven wrong. Thus it would be a good scientific hypothesis.
Laws & Theories
• When a hypothesis has been tested over and over again and found to be correct it can become a law.
• A theory is a synthesis or collection of a vast amount of information which includes well-tested and verified hypotheses.
Laws & Theories
• When a hypothesis has been tested over and over again and found to be correct it can become a law.
• Explains WHAT will happen.
• A theory is a synthesis or collection of a vast amount of information which includes well-tested and verified hypotheses.
• Explains WHY something happens.
Laws & Theories
• When a hypothesis has been tested over and over again and found to be correct it can become a law.
• Explains WHAT will happen.
• The strength of gravity depends on the mass of the object and its diameter is a law of gravity
• A theory is synthesis or collection of a vast amount of information which includes well-tested and verified hypotheses.
• Explains WHY something happens.
• Objects with mass warp space causing the effect we see as gravity is a theory of gravity
Just like a scientific fact; laws, theories and hypotheses must be
changed when the evidence shows them to be wrong !!!!!
Just like a scientific fact; laws, theories and hypotheses must be
changed when the evidence shows them to be wrong !!!!!
This is how science works. Scientists constantly test their ideas and change them when it is needed.
A Scientific Method
Scientists use an organized set of steps to test and verify hypotheses. From these hypotheses they either form new theories or
laws, or they modify existing theories or laws.
While the next few slides give you an idea of what a scientific method might look like, there is no one recipe that is used. All
scientific methods should include the following steps.
A Scientific Method
1) Recognize a problem.
A Scientific Method
1) Recognize a problem.
This could come from your boss or teacher.
A Scientific Method
1) Recognize a problem.
This could come from your boss or teacher.
This could come from general observations.
A Scientific Method
1) Recognize a problem.
This could come from your boss or teacher.
This could come from general observations.
This could come from your natural curiosity.
A Scientific Method
1) Recognize a problem.
This could come from your boss or teacher.
This could come from general observations.
This could come from your natural curiosity.
Either way it is important to have a defined problem to work on.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
An educated guess based on prior knowledge or after doing research on the problem.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
An educated guess based on prior knowledge or after doing research on the problem.
Remember, there must be a way to prove the hypothesis wrong.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
If the hypothesis is true, what would I observe ?
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
If the hypothesis is true, what would I observe ?
Can I design an experiment to test these predictions ?
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
Identify Variables & Design an Experiment
Identifying VariablesIdentifying Variables&&
Designing Designing InvestigationsInvestigations
A Variable is anything A Variable is anything that can change in an that can change in an
experiment.experiment.There are three types of variables that an
experimenter must deal with when designing an experiment.
Independent VariableIndependent Variable Dependent VariableDependent Variable
ControlControl
3 Kinds of Variables3 Kinds of Variables
Independent Variable – Independent Variable – something that is changed by something that is changed by the scientistthe scientist What is testedWhat is tested What is manipulatedWhat is manipulated
3 Kinds of Variables3 Kinds of Variables
Dependent Variable – something Dependent Variable – something that might be affected by the that might be affected by the change in the independent variablechange in the independent variable What is observedWhat is observed What is measuredWhat is measured The data collected during the The data collected during the
investigationinvestigation
3 Kinds of Variables3 Kinds of Variables
Controlled Variable – a variable Controlled Variable – a variable that is not changedthat is not changed Also called constantsAlso called constants Allow for a “fair test”Allow for a “fair test”
For Example:For Example:
Students of different ages Students of different ages were given the same jigsaw were given the same jigsaw
puzzle to put together. puzzle to put together. They were timed to see how They were timed to see how
long it took to finish the long it took to finish the puzzle.puzzle.
Identify the variables in Identify the variables in this investigation.this investigation.
What was the independent What was the independent variable?variable?
Ages of the studentsAges of the studentsDifferent ages were tested Different ages were tested by the scientistby the scientist
What was the dependent variable?What was the dependent variable?
The time it took to put the The time it took to put the puzzle togetherpuzzle togetherThe time was observed and The time was observed and measured by the scientistmeasured by the scientist
What was a controlled variable?What was a controlled variable?
Same puzzleSame puzzleAll of the participants were All of the participants were tested with the same puzzle.tested with the same puzzle.
It would not have been a fair It would not have been a fair test if some had an easy 30 test if some had an easy 30 piece puzzle and some had piece puzzle and some had a harder 500 piece puzzle.a harder 500 piece puzzle.
Another example:Another example:
An investigation was done with An investigation was done with an electromagnetic system made an electromagnetic system made from a battery and wire wrapped from a battery and wire wrapped around a nail. Different sizes of around a nail. Different sizes of nails were used. The number of nails were used. The number of
paper clips the electromagnet paper clips the electromagnet could pick up was measured.could pick up was measured.
What are the variables in this What are the variables in this investigation?investigation?
Independent variable:Independent variable:
Sizes of nailsSizes of nailsThese were changed by the These were changed by the scientistscientist
Dependent variable:Dependent variable:
Number of paper clips Number of paper clips picked uppicked upThe number of paper clips The number of paper clips observed and counted observed and counted (measured) (measured)
Controlled variables:Controlled variables:
Battery, wire, type of nailBattery, wire, type of nail None of these items were changedNone of these items were changed
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
Identify Variables & Design an Experiment
Collect and organize data.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
Identify Variables & Design an Experiment
Collect and organize data.
Draw conclusions : Was the hypothesis correct, incorrect, or was the experiment inconclusive ?
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
5) Formulate the simplest general rule.
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
5) Formulate the simplest general rule.Should organize the hypothesis, the prediction, the experimental steps and the
conclusion
A Scientific Method
1) Recognize a problem.
2) Form a hypothesis.
3) Predict consequences of the hypothesis.
4) Perform an experiment to test predictions.
5) Formulate the simplest general rule.Should organize the hypothesis, the prediction, the experimental steps and the
conclusion
Results should be published so your work can be reviewed by other scientists.