How much water makes a bottle flip land best?
- 💧 Water
- 🧽 A bit messy
My hypothesis
If I change how much water is in the bottle, then how many of 10 flips land upright will ______, because ______.
You fill in the blanks. Think about where the water goes while the bottle is in the air, and where it is when the bottle lands. A guess is a good because: the test finds out.
Change, measure, keep the same
CHANGE
how much water is in the bottle: A quarter full, Half full, Three-quarters full
MEASURE
how many of 10 flips land upright, in landings, of 10
KEEP THE SAME
- the same bottle with its cap on tight
- flipping it so it turns over once
- the same clear table
- ten flips in every try
Scientists call the thing you change the independent variable and the thing you measure the dependent variable. The things you keep the same are the controls: if one of them changed too, you wouldn't know which change made the difference. Try each of the 3 levels 3 times.
What you need
- An empty plastic bottle: 1, with its cap
- Water from the tap
- Masking tape, to mark lines
- A sponge or cloth, for wiping up
- 📏 A ruler
Steps
- Measure the bottle's height, and tape marks a quarter, half and three-quarters of the way up.
- Fill the bottle with tap water to the quarter mark and screw the cap on tight.
- Clear a table of anything breakable, and wipe it dry.
- Hold the bottle by its neck, flip it so it turns over once, and try to land it upright on the table.
- It only counts if the bottle stands on its bottom and stays up.
- Flip it ten times, and write the number of landings in your table under Try 1.
- Do ten more flips for Try 2 and ten more for Try 3.
- Add water to the half mark, cap it tight, and do three tries of ten flips.
- Add water to the three-quarter mark, cap it tight, and do three more tries of ten flips.
- Find the mean landings for each amount and draw a line graph.
- Wipe up every spill when you are done.
Every step is one you can do yourself, with a grown-up nearby. Write each number down straight away, in the table below, so nothing is lost.
Your results table
Name ______________________ Fair day ____________
Question: How much water makes a bottle flip land best?
I changed: Water in the bottle I measured: how many of 10 flips land upright (landings, of 10)
| Water in the bottle | Try 1 (landings, of 10) | Try 2 (landings, of 10) | Try 3 (landings, of 10) | Mean |
|---|---|---|---|---|
| A quarter full | ||||
| Half full | ||||
| Three-quarters full |
MY GRAPH (a line graph: water in the bottle along the bottom, landings, of 10 up the side)
What I noticed: ______________________________________________
From 4th grade, add the tries for each level and divide by how many there were: that's the mean, and it goes in the last column. Then draw a line graph, because the thing you change is a number that goes up.
Name ______________________ Fair day ____________
Question: How much water makes a bottle flip land best?
If I change how much water is in the bottle, then how many of 10 flips land upright will ________________, because _____________________________________________
| I CHANGE | I MEASURE | I KEEP THE SAME |
|---|---|---|
| Water in the bottle: A quarter full, Half full, Three-quarters full | how many of 10 flips land upright (landings, of 10) |
|
What I think will happen, in my own words:
Name ______________________ Fair day ____________
Question: How much water makes a bottle flip land best?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: How much water makes a bottle flip land best?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: How much water makes a bottle flip land best?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: How much water makes a bottle flip land best?
My hypothesis was ☐ right ☐ partly right ☐ not right.
I know because my numbers show:
What surprised me, or what might have gone wrong (7th and up):
Next time I would test:
Idea: Change a second thing: try the same three amounts in a tall thin bottle and a short wide bottle, and graph the landings for both.
Why it works
In the air the water sloshes around inside the bottle, and when the bottle comes down it ends up at the bottom, which puts the weight low. A bottle with its weight low is hard to tip over, so it can stay upright. With too little water there is little weight, and with too much the bottle is hard to turn, so there is often a best amount in the middle.
Going further (7th and up): Change a second thing: try the same three amounts in a tall thin bottle and a short wide bottle, and graph the landings for both.
Board layout
- ❓ Question (10 × 8 in): How much water makes a bottle flip land best?
- 💭 Hypothesis (10 × 9 in): If I change how much water is in the bottle, then how many of 10 flips land upright will ______, because ______.
- 🧺 Materials (10 × 12 in): 4 things: see your list.
- 🪜 Steps (22 × 9 in): 11 steps, three tries at each level.
- 📊 Results (22 × 16 in): Your table (Water in the bottle down the side, tries across) and your line graph.
- ✅ Conclusion (10 × 14 in): My hypothesis was right / partly right / not right. I know because…
Materials to list: An empty plastic bottle; Water from the tap; Masking tape, to mark lines; A sponge or cloth, for wiping up.
Bring photos or drawings of your test. Nothing wet, hot, powered or alive on the table.
This project at your grade
| 1st–3rd grade | Tries: three at each level (one is fine at a first fair). The table: levels and tries, numbers or pictures. The graph: a picture, or a simple bar graph. The conclusion: what happened, in their words. |
|---|---|
| 4th–6th grade | Tries: three at each level. The table: units in the header and a mean column. The graph: a bar graph, or a line for a number that grows. The conclusion: right, partly or not, and the numbers that show it. |
| 7th grade and up | Tries: three or more at each level. The table: a mean for every level of both tests. The graph: a graph with two lines or two sets of bars. The conclusion: the numbers, what might have gone wrong, and a next question. Second variable: try the same three amounts in a tall thin bottle and a short wide bottle, and graph the landings for both. |
From 4th grade up, the table gets a mean column. See every project for 3rd grade, or print a blank results table.
What a judge will ask
- What did you change, and what did you measure? I changed how much water is in the bottle and measured how many of 10 flips land upright, in landings, of 10.
- What did you keep the same, and why does that matter? I kept the same bottle with its cap on tight and flipping it so it turns over once the same, so the only difference was how much water is in the bottle.
- How many times did you test it? 3 times at each of my 3 levels.
- If you did it again, what would you change or test next? I'd try the same three amounts in a tall thin bottle and a short wide bottle, and graph the landings for both.
Make it yours
Keep this project on this device and Peabody counts down to your fair day, with a plan for each day. Nothing is sent anywhere.
Try next
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