Steps of the Scientific Method
Variables
Experiments
Vocabulary
Laws vs. Theories
100
John writes down the distances the paper airplane travels, calculates the average, and makes a bar graph.
What step of the scientific method does this describe?
Collect and Analyze Results
100
What is a variable?
Something that changes
100
Ryan states that "The only way for a scientist to obtain information and knowledge is by doing experiments."
Is Ryan's statement correct? Explain.
Ryan's statement is not correct since not all scientists do experiments. Many scientists rely on direct observation and discovery to obtain their data such as astronomers, paleontologists, and marine biologists
100
The variable that is being tested in the experiment. Also known as the "test variable".
Independent Variable
100
Must be supported by data and evidence
Both
200
"If I replace the battery in my car, then my car will get better gas mileage" This statement is an example of what step of the scientific method?
A Hypothesis (If, Then Statement)
200
John wants to test which size of soccer (football) ball is easiest to juggle with his feet. He tests a size 3, size 4 and a size 5 ball. He then counts the seconds the ball stays in the air for each of the trials.
What is the dependent variable?
The number of seconds the ball stays in the air
200
What are two ways that the results of an experiment can be made more reliable?
Repetition of the experiment
Replication of the experiment and comparing results
Adding more test subjects
Accurately writing and following the experimental procedure
200
The variable being measured in the experiment. Also referred to as the "outcome variable"
Dependent Variable
200
Explains why something happens
Theories
300
"According to my experiments, the Energizer maintained its voltage for approximately 3% longer period of time than the Duracell battery. My hypothesis was that Energizer would last the longest in all of the devices tested. My results do support my hypothesis."
The statement above is an example of what step in the scientific method?
Conclusion
300
John wants to test which size of soccer (football) ball is easiest to juggle with his feet. He tests a size 3, size 4 and a size 5 ball. He then counts the seconds the ball stays in the air for each of the trials.
What is the independent variable?
The size of the soccer ball
300
Mark wants to see how salt will affect the height of sunflower plants. He gives one group of plants salt water and another group of plants plain water. After a two week period, the height is measured.
What is the experimental and control group in this experiment?
Experimental group- plants that receive salt water
Control group- plants that receive plain water
300
Explain the difference between repetition and replication of an experiment.
Repetition- When someone does an experiment more than once.
Replication- When another person copies an experiment that has already been done.
300
States what will happen. Describes a repeating pattern that we can observe in nature. For example, "The force of an object is equal to its mass times acceleration F = MA"
Law
400
Kristin makes the hypothesis
"Our universe is surrounded by another, larger universe that we can have absolutely no contact with."
What is the problem with Kristin's hypothesis?
it is not testable. There are no observations that a scientist can make to tell whether or not the hypothesis is correct
400
John wants to test which size of soccer (football) ball is easiest to juggle with his feet. He tests a size 3, size 4 and a size 5 ball. He then counts the seconds the ball stays in the air for each of the trials.
What would be a controlled variable in this experiment?
The brand of soccer ball
The same person juggling the ball
The technique used to juggle the ball
400
Class Question
About how many more muffins were sold on Saturday compared to Wednesday
8 more muffins
14-6 = 8
400
What is a controlled variable in an experiment?
A controlled variable is a factor that the researcher keeps the same in the experiment so that results of the experiment are not effected.
400
Can be modified (changed) if new evidence no longer supports it
Both laws and theories
500
Class Question
What are the seven steps of the scientific method? (in the correct order)
Ask a question , Research, Hypothesis, Experiment, Collect and analyze results, Conclusion, Communicate results
500
Researchers wanted to study the hatching rate of fruit flies at different temperatures. . The trays were placed in separate incubators at 30, 50, and 70 degrees Celsius. The researchers counted the number of eggs that hatched in each tray after 24 hours.
What is the independent variable?
The temperature
500
How many people had a favorite movie type of Romance and Comedy combined?
10
500
What is the difference between the experimental group and control group in an experiment?
Experimental group- receives what is being tested
Control group- does not receive what is being tested
500
Class Question
What are three things that laws and theories have in common?
Both are supported by evidence
Both are accepted by the majority of scientists
Both can be changed if new evidence no longer supports it
Both are based on tested hypotheses