Which wrap muffles the sound of a ticking timer best?
- ✅ Nothing sharp, hot or small
My hypothesis
If I change what the timer is wrapped in, then how far away you can still hear it will ______, because ______.
You fill in the blanks. Think about what soft, fluffy things do when something bumps into them. A guess is a good because: the test finds out.
Change, measure, keep the same
CHANGE
what the timer is wrapped in: Nothing, Paper towels, A wool sock, Bubble wrap
MEASURE
how far away you can still hear it, in cm
KEEP THE SAME
- the same ticking timer in the same shoebox
- the same listener
- the same quiet room
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 4 levels 3 times.
What you need
- A stopwatch or a kitchen timer: a kitchen timer that ticks, or a clock that ticks
- A shoebox
- Paper towels
- Something wool: a sock, a hat or a sweater: a wool sock
- Bubble wrap
- A tape measure, or a long ruler
- Masking tape, to mark lines: for marks on the floor
- 🩹 Tape
Steps
- Start the timer ticking, put it in the shoebox with nothing round it, and close the lid.
- Stand right next to the box. You should hear the ticking.
- Take one step back at a time and listen with your eyes shut.
- Stop when you can't hear it any more, and put a tape mark at your toes.
- Measure from the box to the mark, and do it two more times.
- Wrap the timer in paper towels, put it back in the box and test it three times.
- Test it three times in the sock, and three times in bubble wrap.
- Draw a bar for each wrap. The shortest bar muffled the sound best.
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: Which wrap muffles the sound of a ticking timer best?
I changed: Wrap I measured: how far away you can still hear it (cm)
| Wrap | Try 1 (cm) | Try 2 (cm) | Try 3 (cm) | Mean |
|---|---|---|---|---|
| Nothing | ||||
| Paper towels | ||||
| A wool sock | ||||
| Bubble wrap |
MY GRAPH (a bar graph: wrap along the bottom, cm 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 bar graph, one bar for each thing you tried.
Name ______________________ Fair day ____________
Question: Which wrap muffles the sound of a ticking timer best?
If I change what the timer is wrapped in, then how far away you can still hear it will ________________, because _____________________________________________
| I CHANGE | I MEASURE | I KEEP THE SAME |
|---|---|---|
| Wrap: Nothing, Paper towels, A wool sock, Bubble wrap | how far away you can still hear it (cm) |
|
What I think will happen, in my own words:
Name ______________________ Fair day ____________
Question: Which wrap muffles the sound of a ticking timer best?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: Which wrap muffles the sound of a ticking timer best?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: Which wrap muffles the sound of a ticking timer best?
| Date | What I did | What I saw | What I think |
|---|---|---|---|
Name ______________________ Fair day ____________
Question: Which wrap muffles the sound of a ticking timer 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: use one, two and three layers of the best wrap, and see how much each layer adds.
Why it works
Sound travels as a shaking that passes from the timer into the air around it. Soft, fluffy things like wool and bubble wrap are full of little pockets of air that soak up the shaking, so less of the sound gets out and you have to stand closer to hear it.
Going further (7th and up): Change a second thing: use one, two and three layers of the best wrap, and see how much each layer adds.
Board layout
- ❓ Question (10 × 8 in): Which wrap muffles the sound of a ticking timer best?
- 💭 Hypothesis (10 × 9 in): If I change what the timer is wrapped in, then how far away you can still hear it will ______, because ______.
- 🧺 Materials (10 × 12 in): 7 things: see your list.
- 🪜 Steps (22 × 9 in): 8 steps, three tries at each level.
- 📊 Results (22 × 16 in): Your table (Wrap down the side, tries across) and your bar graph.
- ✅ Conclusion (10 × 14 in): My hypothesis was right / partly right / not right. I know because…
Materials to list: A stopwatch or a kitchen timer; A shoebox; Paper towels; Something wool: a sock, a hat or a sweater; Bubble wrap; A tape measure, or a long ruler; Masking tape, to mark lines.
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: use one, two and three layers of the best wrap, and see how much each layer adds. |
From 4th grade up, the table gets a mean column. See every project for 2nd grade, or print a blank results table.
What a judge will ask
- What did you change, and what did you measure? I changed what the timer is wrapped in and measured how far away you can still hear it, in cm.
- What did you keep the same, and why does that matter? I kept the same ticking timer in the same shoebox and the same listener the same, so the only difference was what the timer is wrapped in.
- How many times did you test it? 3 times at each of my 4 levels.
- If you did it again, what would you change or test next? I'd use one, two and three layers of the best wrap, and see how much each layer adds.
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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