The Scientific Method Makes Up 40% of Science STAARs
Problem for an Experiment: CSCOPE’s Incorrect Example
How does an applied force, such as a push, affect a CD hovercraft?
- A push is not a type of force, instead it describes a force that moves an object away from you.
- The problem doesn’t identify how the force will affect the hovercraft?
The dependent variable is not identified.
Problem: Correct Example
What effect does an applied force have on the average speed of a CD hovercraft?
Independent Variable: This is what you are changing. This variable causes something to happen. It should be measurable.
Applied force on the hovercraft is the Independent Variable.
Dependent Variable: This is what changes as the independent variable changes. In other words, as the force on the hovercraft changes, the average speed of hovercraft may change. (Note the word may. Whether it does or not is what you discover in the investigation.)
Average speed of the hoovercraft is the dependent variable.
Hypothesis: CSCOPE’s Incorrect Example
If a greater force is applied to a CD hovercraft, then the faster it will move.
Hypothesis: Correct Example
Hypothesis is what you think will happen. This is not a wild guess. Instead, while a guess, it is based on previous knowledge you have about moving objects.
While there is no rule other than one your teacher might have, about writing a hypothesis. This is an example that many science fair judges approve of.
Hypothesis for the Example Problem:
If force causes the hovercraft to move, then as the force applied to the hovercraft increases the craft’s speed increases.
Yes, it is a bit wordy, but it includes all the information needed.
The hypothesis starts by giving boundaries for the hypothesis–If force causes the craft to move, then——
The hypothesis identifies how the force is expected to affect the hovercraft–
An increase in force applied causes an increase in the average speed of the craft