Family mode

Watch this one together

~5 min · materials: none (optional: a ball on a string or a key on a shoelace to whirl safely)

Why does a ball on a string fly off the second you let go?

Swinging a conker/yo-yo or a bucket of water on a rope, or letting go of a playground merry-go-round / a sled swung in a circle — and the classic "hammer throw / discus" at sports day: the athlete spins then releases and it flies off sideways, not straight out. Wet-dog shake or spin-drying salad also land the "things fly off a spinning thing" feeling.

Talk about it

  • Point the way you think the ball will fly before we cut the string, then see if you were right.
  • Why does your hand have to keep pulling the whole time the ball spins?
  • A hammer thrower spins and lets go — which way does the hammer fly? Guess, then act it out.
Watch it together

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