For you to do
You'll make a paper rotor that spins as it falls — like a maple seed. Then you'll change ONE thing (blade length, or paperclips) and see how the fall time changes.
Grown-up help
All on your own. The only sharp thing is scissors — you've got this.
Make it
- Cut a strip of paper about 3 cm wide and 15 cm long.
- Cut a slit halfway down the middle of the top so you have two flaps. Fold one flap toward you and one away — these are the blades.
- Fold the bottom up and add a paperclip so it drops point-down.
Run the test
Drop it from the same height (stand on the same step each time) and time how long it takes to land. Do three drops and take the middle number.
- Change one thing: make the blades shorter, OR add a second paperclip — not both.
- Time three more drops and compare.
What's happening
Push further
Can you design the SLOWEST-falling helicopter using one sheet of paper and one paperclip? Write down each version you try.
Air pushing on the angled blades makes them spin, and that spinning **drag** slows the fall. Heavier weight (more paperclips) makes it fall faster; longer blades catch more air and fall slower. Because you only changed one **variable** at a time, you know which change caused the difference.