The Method
The first step in the scientific method
Question
What is the definition of a dependent variable?
What changes because of what the scientist did
What is the definition of an independent variable?
What the scientist changes in the experiment
What is the definition of the controlled variable?
The things that stay the same in the experiment
Create a hypothesis for this question...
Will changing the amount of cheese on a mousetrap make it easier to catch a mouse?
If I use more cheese, then I will catch a mouse faster.
This step comes after you make your question. You may need other resources to help you.
Background research
Does heating water allow it to dissolve more sugar?
What is the dependent variable?
The amount of sugar that dissolves
Does heating water allow it to dissolve more sugar?
What is the independent variable?
Temperature of the water
Does heating water allow it to dissolve more sugar?
What is one controlled variable?
The amount of water used
What kind of material (plastic sheet, piece of cloth, or newspaper) will make the best parachute?
If I make a parachute our of plastic, then the parachute will fall to the ground more slowly.
A prediction- If I do this, then this will happen.
Hypothesis
Does fertilizer make a plant grow bigger?
What is the dependent variable?
Growth of the plant
Does fertilizer make a plant grow bigger?
What is the independent variable?
the amount of fertilizer
Does fertilizer make a plant grow bigger?
What is one controlled variable for this experiment?
the type of fertilizer
What kind of cup (styrofoam, paper, or glass) will keep liquid hot the longest?
If I use a styrofoam cup to hold hot water, then the water will stay hot longer then the other two cups.
This is the last step where you revisit your data and hypothesis and explain whether your data answered your hypothesis.
Conclusion
Does an electric motor turn faster if you increase the voltage?
What is the dependent variable
the speed of the motor rotations
Does an electric motor turn faster if you increase the voltage?
What is the independent variable in the experiment?
The voltage of the electricity
Does an electric motor turn faster if you increase the voltage?
What is one controlled variable for this experiment?
the same type of motor
Which brand of chips (Lays, Ruffles, or Utz) has the most chips in a bag?
If I count the chips in the same size bags of three different chip brands, then the Utz bag will have the most chips in it.
This step is where you look at your data to see if you need to collect more
Analysis
How much water flows through a faucet at different openings?
What is the dependent variable?
The amount of water flowing
How much water flows through a faucet at different openings?
What is the independent variable?
the faucet's opening (closed, half open, and fully open)
How much water flows through a faucet at different openings?
What is one controlled variable in the experiment?
the same kind of faucet in the same room
Which type of sandpaper will cause the most friction?
If I test three kinds of sandpaper in a marble roller coaster, then the one that is the roughest will cause the marble to travel the slowest.