• Question: if Graphene was to be dropped from the edge of the atmostphere what would happen

    Asked by anon-201751 to George on 6 Mar 2019.
    • Photo: George Fulton

      George Fulton answered on 6 Mar 2019:

      Nice question! In short, I think not much!

      Graphene is a single layer of carbon atoms in a honeycomb structure. This makes graphene very very light. If you dropped graphene from the top of the atmosphere, it would fall towards the earth because of gravity, but because it is so so light, it won’t fall very quickly at all! This is because air resistance acts to stop it and it doesn’t take a lot of resistance to stop something so light.

      This is true for all light things and it is why if an ant dropped off the eiffel tower it would survive, while an elephant would certainly die. The ant and the graphene will fall really slowly to earth due to the air resistance.

Comments

  • Photo: Andy

    Andy commented on :

    Good answer, @George! Graphene is pretty cool, but we can only make it in small flakes at present, and it will always (by definition) be only one layer of atoms thick. Dropping it through the atmosphere would just lead to it getting blown around, a *lotMATOMO_URL

    I guess maybe the question was asking about what happens if you hit some graphene really, really hard. It’s very strong (for its size) so moderately hard impacts of small things would bounce off. At some point they’d puncture the sheet. And at some extreme impact velocity, I guess they’re change the material structure, fold the single layer into something 3D, and you’d get graphite or maybe even some bits of diamond. And at really, really, really high velocities you’ve built a particle collider and can do heavy-ion nuclear physics with carbon nuclei. These extreme things would require a lot more energy than you’d get by dropping from the edge of the atmosphere, though: more like “blown out of a supernova”.