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  • I recently received this question via email: Hello there,

  • Imagine we build a giant ring around the whole globe, perfectly round, no ups and downs.

  • What you didn't know is that i installed explosives all around on each pole holding it up, and

  • then boom.

  • All the poles break at the same time.

  • What will happen to the ring?

  • Will it just sit there in the air?

  • Or will it fall down?

  • Will it start spinning like crazy?

  • Best regards, Martin from Sweden.

  • First off, Martin, that was sneaky.

  • I cannot condone secretly installing explosives on poles holding up infrastructure projects.

  • Second, I have a feeling you might really like the planet Saturn.

  • And Third, fun question!

  • The answer depends a lot on how strong the ring is, but in general you've touched upon

  • an idea called symmetry breaking.

  • As you've realized, a perfectly symmetric ring doesn't have any particular reason to

  • fall or break in any one point!

  • Like a perfectly balanced pencil, which way will it fall?

  • Anyway, if the ring is really really strong, then it should just stay exactly where it

  • is, "hovering", though that actually means being held up by its own strength, because

  • each part will be gravitationally pulled toward the center of the earth, and since those forces

  • are spread equally around the ring in a symmetric way theyll cancel out.

  • Like how in tug of war if both sides pull the same amount the rope won’t move).

  • Now, if the ring’s not sufficiently strong, it might buckle in places and become scrunched

  • up, like the coins that my friend Dianna shrunk by putting them in a very strong, very quickly

  • changing magnetic field.

  • It’s interesting to note that the properties of circumferences mean you’d only have to

  • take out a few meters for the ring to be small enough to just lie on the ground.

  • As forwill it start spinning like crazy”?

  • I think you might be referring to the idea that the earth is spinning to the eastunderneath

  • the ringwell, I have a whole other video about that, that you should definitely check

  • out.

  • Thanks for your question, and stay away from

  • the high explosives.

I recently received this question via email: Hello there,


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B1 中級

環繞地球? (Ring AROUND the Earth?)

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    林宜悉 發佈於 2021 年 01 月 14 日