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If you could throw an object very high, so high that it would take a few
hours to fall back to earth. Would it land in the same location it was
thrown from or would the fact that the Earth is spinning mean that the
object would land in a new location.
Thanks for any help.

Originally Posted by Bear

If you could throw an object very high, so high that it would take a few
hours to fall back to earth. Would it land in the same location it was
thrown from or would the fact that the Earth is spinning mean that the
object would land in a new location.
Thanks for any help.

Try it - just a gentle lob will do - but use something heavy so as not to be deflected by wind - and run fast. Alternatively you could visit Pisa and repeat a famous experiment of old - it wont matter if the object is rising or falling;-)
Nytecam

b)

In article , Bear
wrote:

If you could throw an object very high, so high that it would take a few
hours to fall back to earth. Would it land in the same location it was
thrown from or would the fact that the Earth is spinning mean that the
object would land in a new location.
Thanks for any help.



Interesting question, if you negated air effects, then Newtonian
physics would say that what goes straight up comes straight down.
However, if the object went up really high, then the effects of frame
dragging (the effect of any rotating mass on space/time/gravity) would
ensure the object would come down in a slightly different place, as the
Earth would have rotated round under the ejected mass's space/time
location. See http://en.wikipedia.org/wiki/Frame_dragging

And if its proved experimentally then Einstein was right about another
aspect of general relativity!

Clear Dark and Steady Skies

Torcuill

"Torcuill Torrance" wrote in
message
s.com__removelihgt...
In article , Bear
wrote:

If you could throw an object very high, so high that it would take a few
hours to fall back to earth. Would it land in the same location it was
thrown from or would the fact that the Earth is spinning mean that the
object would land in a new location.
Thanks for any help.



Interesting question, if you negated air effects, then Newtonian
physics would say that what goes straight up comes straight down.

No, it would be accellerated towards the centre of mass of the Earth, which
is not quite the same thing with a rotating planet. The point it was thrown
from would continue on its normal path of rotation. The object would have an
initial velocity of the tangential velocity of rotation plus its vertically
thrown velocity, and then would follow a curved path until it touched Earth
again. I'm 99% certain b).

In ,
Andy Guthrie typed:
The
object would have an initial velocity of the tangential velocity of
rotation plus its vertically thrown velocity, and then would follow a
curved path until it touched Earth again. I'm 99% certain b).


Or would miss the earth on its way back down and continue in an elliptical
orbit.

Er...I think.

Jo

"Jo" wrote in message
...
In ,
Andy Guthrie typed:
The
object would have an initial velocity of the tangential velocity of
rotation plus its vertically thrown velocity, and then would follow a
curved path until it touched Earth again. I'm 99% certain b).


Or would miss the earth on its way back down and continue in an elliptical
orbit.

Er...I think.


I'm no rocket scientist, ahem, but I reckon that after departing from a
point on the surface it could not achieve an elliptical orbit without some
further powered adjustments.

thanks for the answers guys

Wasn't it Andy Guthrie who wrote:

I'm no rocket scientist, ahem, but I reckon that after departing from a
point on the surface it could not achieve an elliptical orbit without some
further powered adjustments.

No. Any thrown object follows an elliptical orbit. What they told us in
school about a thrown object following a parabola would be true if we
lived on a flat earth where lines of gravity were parallel. For objects
thrown only a short distance, the difference between a parabolic an
elliptical trajectory is negligible because gravity is close to be
parallel.

In message , Andy Guthrie
writes

"Torcuill Torrance" wrote in
message
us.com__removelihgt...
In article , Bear
wrote:

If you could throw an object very high, so high that it would take a few
hours to fall back to earth. Would it land in the same location it was
thrown from or would the fact that the Earth is spinning mean that the
object would land in a new location.
Thanks for any help.



Interesting question, if you negated air effects, then Newtonian
physics would say that what goes straight up comes straight down.

No, it would be accellerated towards the centre of mass of the Earth, which
is not quite the same thing with a rotating planet. The point it was thrown
from would continue on its normal path of rotation. The object would have an
initial velocity of the tangential velocity of rotation plus its vertically
thrown velocity, and then would follow a curved path until it touched Earth
again. I'm 99% certain b).

The question of velocity of rotation was argued ad nauseam on
alt.babylon5.uk some years ago, and I'm fairly sure the answer was that
there isn't any. Once the object is thrown it follows its own path,
while the Earth rotates under it. So it won't come down where it was
launched.
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