Why does a ball on a string fly off the second you let go?
Open for the projector Present it step by step
Classroom mode
A question for the whole room
One story to open. A room full of ideas to test.
Ready in three steps
- Open the story.Read and try the first pages together.
- Pause for a prediction.At the story’s question, read its choices aloud. Invite a vote and ask, “What makes you think that?”
- Run it. Watch. Wonder.Choose the class’s prediction, run the experiment, and compare what happened with your guesses.
Different guesses are welcome. The experiment gives everyone something to rethink.
Something to put on paper
A one-page prediction and observation sheet. No answers included.
After the experiment: discussion notes
Talk about what happened
- Predict first: when the string is cut, will the ball go straight outward from the center or sideways? Vote, then watch.
- If there is no force pushing the ball outward, what is the only real force acting on it while it circles? Where does that force point?
- Predict what changes about the ball's path the instant the string is gone, and what happens a moment later because of gravity.
Where it shows up in real life
- A hammer thrower or discus athlete spinning and releasing at sports day
- Swinging a conker or yo-yo on a string, or a bucket of water on a rope
- Letting go on a spinning playground merry-go-round and feeling flung sideways
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