• Question: If i dig a hole through the Earth (from one end to another), then if i jump through it, will i fall out the other side of the earth ?

    Asked by sodiumpolyacrylate to David, James, Mike, Suze, Will on 21 Jun 2011.
    • Photo: Suze Kundu

      Suze Kundu answered on 18 Jun 2011:

      You might be able to, but the core of the Earth is REALLY hot, and I am a little bit worried that you might burn up before that happened. And besides, it’s a really long way through! You’d be starving before you even made it to the warm layers of the Earth! Definitely not something to try at home 😛

      Would you even want to?! Maybe you could just fly to the other side when you’re older, if you work really hard!

    • Photo: James Marrow

      James Marrow answered on 20 Jun 2011:

      Assuming the earth was cold, you’d be going through a changing gravitational pull. It should be possible to work out how much this would accelerate and then decclerate you, and you’d then have to think about wind resistance (or do you want to get rid of the air as well?).

      If there was no air, I think you might just come out the other side (but keep your elbows tucked in)

    • Photo: William Eborall

      William Eborall answered on 20 Jun 2011:

      A nice quote from the TV show Qi:
      You can get from where you are to anywhere else in the world in exactly 42 minutes and 12 seconds by travelling through the Earth. Theoretically speaking, if there was a hole that went through the planet and you jumped down it, it would take you 42 minutes and 12 seconds to fall through to the other side because of the gravity. The maximum speed you can travel at depends on where the tunnel is. This tunnel does not have to grow straight down the middle of the Earth. It can be placed anywhere, and it would still take you the same time to come out of the other end. This is known as a “Gravity train” and while it is not feasible on Earth, it might be on the Moon because it has no molten core, but it would take 53 minutes to travel through it because the gravity is weaker. The people who worked out the information regarding the 42 minutes and 12 seconds were Sir Isaac Newton and Robert Hooke, in a series of letters between them.

    • Photo: Mike Dodd

      Mike Dodd answered on 20 Jun 2011:

      It’s an interesting question. I have to agree with Will there on the Qi quote. Although we have been thinking in the lab whether that would work. As gravity is not a single point and when you get to the centre of the earth, gravity is all around you, so you might just bob around in the centre of the world….. although I’m not going to argue with Sir Isaac Newton

    • Photo: David Ingram

      David Ingram answered on 21 Jun 2011:

      Unfortunately not. Even if you could avoid creating volcano’s and being cooked by the core of the earth, wind resistance would mean you would lose energy and fall back towards the core without coming out – though you might see the sunlight.

      If you want to see what it might be like try playing Portal with two holes in the floor.