Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 03/08/2012 18:30:01

Title: How would objects in tunnels through the Earth behave?
Post by: thedoc on 03/08/2012 18:30:01
Brian Joyce  asked the Naked Scientists:
   
Hi Chris,

Love the show (http://www.thenakedscientists.com/HTML/podcasts/) - been listening (http://www.thenakedscientists.com/HTML/podcasts/) for about a year now.

I have a question ... if a tunnel were to be built that went straight down all the way through the centre of the earth and out the other side, and I stood on one side of that tunnel and dropped something down it, would the item I dropped pick up speed as it fell then stop when it got to the middle of the tunnel (i.e. centre of the earth) or would it go all the way through and shoot out the other side; so someone standing the other side would see the item shoot up into the air as it came out?

If the item were to stop in the middle would it slow down gradually or come to a sudden stop or would it bounce around from one end of the tunnel to the other until finally resting in the middle?

If the tunnel were built on the equator would the item have more chance of hitting the side of the tunnel as the earth spins around rather than if the tunnel went form North Pole to South Pole?

Keep up the good work (http://www.thenakedscientists.com/HTML/podcasts/)!

Thanks
Brian Joyce

What do you think?
Title: Re: How would objects in tunnels through the Earth behave?
Post by: syhprum on 03/08/2012 21:26:07
This subject has been much discussed on this board I suggest you take a look at

http://en.wikipedia.org/wiki/Gravity_train