🚗 Does a steeper ramp make a toy car go farther?

My hypothesis

If I change how high the ramp is, then how far the car rolls will ______, because ______.

🔊 You fill in the blanks. Think about how fast the car is going when it reaches the bottom of the ramp. A guess is a good because: the test finds out.

Change, measure, keep the same

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

• 🚗 A toy car
• 📚 Some books: 3, all about the same thickness
• 📦 Flat cardboard: a long flat piece, about 60 cm
• 🩹 Masking tape, to mark lines
• 📏 A tape measure, or a long ruler

Steps

1. Lean the cardboard on one book to make a ramp on a hard floor.🔊
2. Put a strip of masking tape across the top of the ramp: that's your start line.🔊
3. Put the car's front wheels on the line and let go. Don't push!🔊
4. When it stops, measure from the bottom of the ramp to the front of the car.🔊
5. Write the number in your results table under Try 1.🔊
6. Do it two more times from the same line, and write each one down.🔊
7. Add a second book under the ramp and do three more tries.🔊
8. Add a third book and do three more tries.🔊
9. Find the middle number for each height, and draw your graph.🔊

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

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.

Why it works

🔊 A higher ramp lets the car drop farther before it reaches the floor, so it is going faster at the bottom. A faster car carries more energy, and it rolls farther before rubbing on the floor slows it down. A very steep ramp can bump the car's nose at the bottom, which is why scientists test instead of guessing.

Going further (7th and up): Change a second thing: run the 3-book ramp onto carpet and onto a hard floor, and draw both lines on one graph.

Board layout

This project at your grade

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 how high the ramp is and measured how far the car rolls, in cm.
• What did you keep the same, and why does that matter? I kept the same car and the same floor the same, so the only difference was how high the ramp is.
• 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 run the 3-book ramp onto carpet and onto a hard floor, and draw both lines on one graph.

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

• 🎾 Which floor makes a ball bounce highest?1st–5th grade · 1 day of testing · free🚗 How things move · ✂️ Paper, tape and toys
• ✈️ Which wing shape flies farthest?3rd–8th grade · 1 day of testing · free🚗 How things move · ✂️ Paper, tape and toys

🔨 From the Workshop: this project grows from a Workshop build, with picture steps of its own.