Re: Hollow Earth

["Paul O. Johnson" <pojhome@SWBELL.NET>]

Any object dropped in a hole along Earth's polar diameter would oscillate
with a period of 1.40 hours. This assumes, of course, that Earth's density
is uniform with the average value (which it is definitely not), that the
hole is evacuated, and that the temperature at the center is below the
melting point of the object (also definitely not).

This is not true for such a hole following a non-polar diameter because of
Coliolis forces caused by Earth's rotation.

Paul

----- Original Message -----
From: "Rodney Dunning" <dunnirb4@WFU.EDU>
To: <PHYS-L@lists.nau.edu>
Sent: Saturday, April 22, 2000 12:45 PM
Subject: Re: Hollow Earth


> Jim Green wrote:
>
> > Did I hear/see evidence that "some" planets are hollow -- that someone
> > reported that a ship actually sailed north into a hole at the Earth's
North
> > Pole or the like???   Is there evidence that someone looked through the
N/S
> > holes of a planet????
>
> No, but if there were a hole connecting the poles, and you dropped a ball
in
> it, the ball would exhibit simple harmonic motion. There is class of
idealized
> problems like this at the Halliday-Resnick level of college physics. Maybe
> that's what you're thinking about?
>
> --
> Rodney Dunning
> dunnirb4@wfu.edu
> http://www.wfu.edu/users/dunnirb4