Experimental Questions
Independent Variables
Dependent Variables
Interpreting Data
What's Wrong with This Experiment?
100
One of the most important parts of an experimental question is that it should include an independent variable and a __________________.
What is DEPENDENT VARIABLE?
100
I wanted to know, "Does the color of an M&M affect how quickly the coating dissolves?" This is my independent variable.
What is THE COLOR OF M&M?
100
I wanted to know, "Does the color of an M&M affect how quickly the coating dissolves?" This is my dependent variable.
What is HOW FAST THE COATING DISSOLVES?
100
Draw a data table for this data: I found that Bounty absorbed 14 mL of water on trial 1, 18 mL of water on trial 2, and 20 mL of water on trial 3. Target brand paper towels absorbed 3 mL of water on trial 1, 12 mL of water on trial 2, and 12 mL of water on trial 3.
Check with your teacher for the correct answer.
100
A group of students was trying to figure out how much water is absorbed by different brands of paper towels. They measured the absorbency by squeezing water out of paper towels and into a graduated cylinder. They held the graduated cylinder up to look at how much water was in it.
They should get at eye level with the graduated cylinder to get an accurate measurement.
200
Write an experimental question for this experiment: I want to know if anything could make a can implode faster. I decide to test different temperatures of water to see if that affects how quickly a can implodes.
How does the temperature of the water affect how quickly a can implodes?
200
I asked, "Which brand of paper towels absorbs the most water?" My independent variable is this.
What is BRAND OF PAPER TOWELS?
200
I asked, "Which brand of paper towels absorbs the most water?" My dependent variable is this.
What is HOW MUCH WATER IS ABSORBED?
200
I found that Bounty absorbed 14 mL of water on trial 1, 18 mL of water on trial 2, and 20 mL of water on trial 3. Target brand paper towels absorbed 3 mL of water on trial 1, 12 mL of water on trial 2, and 12 mL of water on trial 3. Which paper towel absorbs more water? (answer only)
According to our data, Bounty absorbed more water. (Note: Target brand had an outlier: 3 mL of water on trial 1. This was way different from trial 2 and 3. We should perform more trials to make sure.)
200
A group of students wanted to find out which type of liquid works best at cleaning pennies. They tried apple juice, lemon juice, and vinegar. They did 1 trial of each liquid and found out that vinegar made 90% of the pennies totally clean, lemon juice made 85% of the pennies totally clean, and apple juice made 20% of the pennies totally clean.
The students only did 1 trial. They should repeat their experiment several times to get reliable data and to make sure they do not have outliers.
300
Write an experimental question for this experiment: I want to know if tomato plants grow bigger tomatoes in full sunlight, half sunlight, or no sunlight.
How does amount of sunlight on a tomato plant affect tomato size?
300
I asked, "How does the shape of a falling object affect the size of a crater?" This is my independent variable.
What is THE SHAPE OF THE OBJECT?
300
I asked, "How does the shape of a falling object affect the size of a crater?" This is my dependent variable.
What is THE SIZE OF THE CRATER?
300
I wanted to see whether the type of soil impacts plant growth. I found that after 2 weeks in clay, my tomato plant grew 2 cm. After 2 weeks in potting soil, my tomato plant grew 10 cm. How does the type of soil impact plant growth? Share the answer AND evidence.
Potting soil leads to more plant growth because the plant in potting soil grew 8 cm taller than (or 5 times as much as) the plant in clay.
300
A group of students wanted to find out which type of liquid works best at cleaning pennies. They tried apple juice, lemon juice, and vinegar. They performed 5 trials. Vinegar cleaned an average of 90% of the pennies (apple juice only cleaned an average of 20%, lemon juice cleaned an average of 85%), so they said vinegar is the BEST liquid for cleaning pennies.
They only tested 3 liquids. They can say that vinegar is better than apple juice and lemon juice, but they can't say it's the best liquid in the world for cleaning pennies. (You could ALSO say that there is not enough of a difference between how vinegar and lemon juice cleaned since 85% and 90% are very close.)
400
Write a HYPOTHESIS for this experimental question: How does the brand of sunglasses affect how much UV light gets through the lenses?
I think that ___________ because ______________. Answers may vary! You MUST include a reason though! Sample answer: I think that the brand of sunglasses does not impact how much UV light gets through the lenses because sunglasses that say "100% UV light blocked" will block light no matter what brand they are.
400
I wanted to know whether the type of soil (clay, dirt from the courtyard, or potting soil) affects how high a plant grows. This is my independent variable.
What is TYPE OF SOIL?
400
I wanted to know whether the type of soil (clay, dirt from the courtyard, or potting soil) affects how high a plant grows. This is my dependent variable.
What is PLANT GROWTH (HEIGHT)?
400
I wanted to find out if the amount of water in a bottle rocket affects how high it goes. I left one bottle empty, filled one bottle completely, and filled one bottle half-way with water. The empty bottle went up 30 meters, the half bottle went up 15 meters, and the full bottle went 1 meter. What can you conclude about how water affects bottle rockets?
An empty rocket will go higher than filling the bottle half with water or full with water. However, we can't say that's the BEST because we still need to try other amounts of water (such as 1/8 full).
400
I wanted to find out if exercise affects learning. I made 2 groups of people. I put 5 people from the cross-country team in the daily exercise group. I put 5 people who don't play any sports in the non-exercise group. After 10 weeks, I looked at how much their grades had improved.
The group is too small. Five people is not enough to make a judgment. Also, you should RANDOMLY assign people to groups so they are mixed. Maybe people who choose to play sports are already getting the benefits of exercise, so they won't show as much improvement.
500
Write an experimental question for this experiment: I want to know more about how exercise impacts learning. I want to have some students exercise for 30 minutes a day for 10 weeks and see if their grades improve. I will have another group who doesn't exercise for 10 weeks.
How does daily exercise impact learning or grades?
500
I asked, "Does a water rocket go higher with 0 fins, 3 fins, or 6 fins?" My independent variable is this.
What is THE NUMBER OF FINS?
500
I asked, "Does a water rocket go higher with 0 fins, 3 fins, or 6 fins?" My dependent variable is this.
What is HOW HIGH THE ROCKET GOES?
500
One group found that Bounty paper towels absorbed 10 mL of water in trial 1, 12 mL of water in trial 2, and 11 mL of water in trial 3. They found that Viva absorbed 15 mL of water in trial 1, 14 mL of water in trial 2, and 13 mL of water in trial 3. How should this group provide EVIDENCE in their conclusion? In other words, how can they summarize their data?
They could say Bounty absorbed an average of 12 mL of water and Viva absorbed an average of 14 mL of water. They could also say Viva absorbed more water than Bounty in all 3 trials. *Special note: Is there enough of a different to declare Viva the most absorbent paper towel?
500
I wanted to find out whether my car window blocks UV light. I used a solar bead which changes from pale yellow to a bright pink when it's in the presence of UV light. I put the solar bead in the car, and it stayed yellow. My car windows must be safe!
I did not use a CONTROL. I should make sure to put the same bead OUTSIDE of the window afterward to make sure it actually changes color in the presence of UV light. Otherwise, it could be a defective bead. Also, I need something to compare the color to.
M
e
n
u