Scientific Experimentation Flashcards
Scientific Method
An organized set of investigation procedures.
Hypothesis
An educated and careful guess
variable usually plotted on the horizontal or x-axis
independent varialble (aka manipulated variable)
graph type used to show some fixed quantity broken down into parts
circle graph (pie chart)
First step in designing an experiment
State the problem
A standard for comparison that helps to ensure that the experimental result is caused by the condition being tested
A Control
factor in an experiment that changes from the manipulation of the independent variable
dependent variable
A factor that does NOT change in an experiment
A constant (aka “controlled variable”)
Studying the effect of one thing on another in order to test a hypothesis is a(n) ____.
experiment
A factor that is manipulated in an experiment to change the dependent variable
independent varialble (aka manipulated variable)
“aka” means
also known as
dependent variable is usually plotted on the
vertical or y-axis
dependent variable is aka
responding variable (IM DR)
independent variable is aka
manipulated variable (IM DR)
“IM DR” is a mnemonic device to help remember
(Independent variable = Manipulated variable) and (Dependent variable = Responding Variable)
Why don’t we draw lines between bars on a bar graph?
There is no data between the bars on a bar graph.
Why do we draw lines between ponts on a line graph?
To represent the expected values of the unmeasured data between the measured points.
Why do we typically avoid putting “breaks” in the axes of graphs?
It distorts the appearance of the data.
When do we put “breaks” in the axes of graphs?
When we are willing to live with the distorted appearance of the data so that we can zoom in on a specific region of the data.
Scientific experiments investigate the effect of one ___________ on another.
variable
Graphs are visual representations of data that help scientists to detect _________ in the data.
patterns
Must be in the form of a statement.
A hypothesis
In a graph showing temperature change of a material over time, temperature change is the ____.
dependent variable
The best type of graph to use to show how some fixed quantity is broken down into parts is_____.
circle graph (pie chart)
When designing an experiment, the first step is to ____.
state the problem
A factor that does NOT change in an experiment is the ____.
constant
A variable that is held constant on purpose is a __________ variable
controlled
plotted on the vertical or y-axis
dependent variable
What is the definition of a derived unit?
A mathematical combination of two or more units.
Why are the points on a bar graph not connected?
There is no data between points that could be graphed.
Explain how the lack of a control in an experiment impacts the experiment.
Without a control, there is no basis for comparison.
Sometimes an experiment has a whole set of hypotheses. The hypothesis that says that changing the independent varialbe will have no effect on the dependent variable is called what?
The Null Hypothesis
True or False.
The “Null Hypothesis” predicts that changes in the independent variable will affect the dependent variable.
False
The Null Hypothesis predicts what relationship between the independent and dependent variables?
No relationship at all.
(Changine the independent variable has not effect on the dependent variable.)
Which one below means the same as a constant?
A Control
A Controlled Variable
A Controlled Variable.
A controlled variable is one of the possible variables in an experiment that you keep the same on purpose.
You are doing an experiment to see if ducks fly faster when listening to music with special “duck” headphones.
You equip 300 ducks with these special headphones and measure their flight speed to be 43mph.
You then conclude that ducks do fly faster with headphones.
What is missing?
A control
You would need “A Control” as a basis for comparison. In other words, you would need to measure the flight speed of a group of ducks without headphones. Then you could compare.
Levels of independent variable
This is the number of different values of the independent variable you use in your lab.
What is the absolute minimum number of levels of independent variable you can use in a lab and still get a useful line graph?
5
(This is the lowest number of levels of independent variable where your data begins speaking back to you.)
