What does a slinky do in space

What happens if you hold an extended stair runner (slinky) in the air and then let it fall? Is it moving down as a whole? Or does something else happen? In the video you can see how the stair runner is doing in free fall. Prepare for a surprise. In general, the stair runner is a great toy that has even been in space. You can find out more about this on this page.

What is needed?

  • a stair runner (metal spiral or slinky)
  • a tennis ball (optional)
  • Chair or table (optional)

What should I do?

Put the tennis ball at one end into the stair runner and hold the other end so that the stair runner can hang freely at some distance from the floor. It is also possible without a tennis ball, but the phenomenon with the ball is better and can also be recognized more easily. If necessary, get on a chair or table. Then drop the stair runner. The following video in English shows the experiment.

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What happened?

If you let the upper end of the stair runner fall, the tennis ball initially remains motionless in the air until the upper end has reached it. Only then does the stair runner fall as a whole towards the earth. The reason: The force of gravity that acts on the tennis ball is just as strong as the spring forces that act upwards. Therefore, there is initially an equilibrium of forces. On the subject of gravity there are numerous other experiments below, some of which have astonishing results.

Further freehand attempts with the stair runner

Longitudinal and transversal waves with the metal spiral

Freehand experiments on the subject of gravity

Air resistance tricked
Who falls faster?
The halyard cord
Drop test with steel and styrofoam
Coin trick