Originally posted by Simon666
Only if he made a near perfect vacuum in the tunnel. If he would not do that, he would stop pretty much in the middle. Under atmospheric conditions,
due to air friction terminal velocity is reached at somewhere around 250 km/h (I don't know the exact figure, you can look it up) depending on
whether you go down with your head down, arms next to your body or legs and arms spread out and body perpendicular to direction of the fall.
My feeling is that it's probably safe to say that this velocity of 250 km/h would be reached.
Originally posted by Simon666If the tunnel would go all the way to the center of the earth and is in connection with the atmosphere, the
air pressure would increase towards the center, just as the pressure in the ocean increases with depth. Hence also your terminal velocity would
decrease several times towards a pretty low speed. Since air is almost one thousand times lighter than water, the increase in pressure would not be as
dramatic as in the ocean but would still be enormous when getting near the center. The air pressure hence could be lethal from a certain point on.
This part ain't necessarily true. It is erroneous to assume that the air pressure would increase in a manner similar to the way water pressure
increases in the ocean depths. After all, the ocean is on the Earth's surface, the hole is not. As anything (air or a person) flows farther into
the depths of the hole, more and more of the Earth's mass is exerting an upward force. Hence, at the center, the air pressure would be zero.
The variation of air resistance against the acceleration of a falling body versus distance into the hole makes for an interesting differential
Originally posted by Simon666Your terminal velocity would further decrease as the force pulling you towards the center becomes ever
smaller only to come to zero when reaching the actual center.
Your terminal velocity would certainly not decrease due to this. F=Ma remember. Any "F" will result in an "a."
Also, this is precisely why the air pressure would decrease. Remember though, with less air pressure, you may be allowed a higher terminal velocity
than the before mentioned 250 km/hr. It's worth repeating here that, although it's true that the force pulling you down would decrease with
distance into the hole, that force would still be operating and would still result in acceleration, albeit a decreasing acceleration. Another
interesting differential equation.
Originally posted by ben91069I think the idea of gravity is very similar to electromagnetism, although they are not the same, but don't
you think at least the formulas for how electomagnetic flux is quite similar to the key to how rotating masses create gravity towards there center?
The only real difference between gravity and electromagnetism is that there is a positive and negative side to electromagnetism. That and the vast
differences in force strength. This lends no validity to your theory about a rotating Earth "creating" gravity though. Rotating currents do not
"create" electromagnetism either. They merely arrange existing EM fields in a manner that results in a single (looking) strong field.
If you take a coil of wire and run current through it, a magnetic field appears with the north pole of the field at the end of the coil found using
the right hand rule. The south pole is at the other end of the coil. A ferromagnetic object placed loosely in the coil could be accelerated out of
the coil by the magnetic force, assuming the current was high enough and the object's mass was small enough.
If you take a coil of extremely durable tubing and somehow pump extremely dense matter through it, a gravitational field appears with the direction of
force at the end of the coil where the matter flows out. Note that the "right hand rule" doesn't apply, a consequence of gravity (unlike
electromagnetism) not having positive and negative associated quantities. An object with mass placed loosely in the coil could be accelerated away
from the coil, assuming the rate of flow (and density) of the "pumped" matter was high enough, and that the object in the coil had small enough
The similarity here is that you are "pumping" the particles that have the necessary associated force (electrons - electromagnetism, particles with
mass - gravity).