Re: Twin Paradox a blasphemy to Relativity

From: TomGee (lvlus_at_hotmail.com)
Date: 02/09/05 

Date: 9 Feb 2005 07:48:24 -0800

PD wrote:
> TomGee wrote:
> > PD wrote:
> > > TomGee wrote:
> > > > Of course you can tell who is moving faster. In order for the
> ship
> > > to
> > > > leave Earth, it must move faster than the Earth is moving. In
> > order
> > > > for the ship to catch up with the Earth on its return to it,
the
> > ship
> > > > must go faster than the Earth.
> > > > TomGee
> > >
> > > You're kidding, right?
> > >
> > > I throw an apple out of a moving car moving at 60 mph and it
leaves
> > the
> > > car with a relative velocity of 5 mph.
> > >
> > >
> > You can throw an apple out of a car at 5mph but you cannot escape
the
> > gravity of Earth at 5mph.
>
> You have no idea what you're talking about. The escape velocity from
> the Earth does not imply that a rocket has to be launched in the same
> direction as the Earth is moving.
>
>
Who said that it does?
>
>
> If the Earth is moving at V with
> respect to the rest of the solar system and the escape velocity of
the
> rocket is v, then if the rocket might have any velocity between V+v
and
> V-v with respect to the solar system and still escape the Earth's
> gravity.
>
> > >
You should tell that to NASA, if you haven't already. They could save
a ton of fuel on their space take-offs.
>
> > >
> > > Now, on the basis of that information, you tell me whether I
threw
> it
> > > forward (so it's going faster than the car) or backward (so it's
> > going
> > > slower than the car).
> > >
> > >
> > Not the same at a rocketship having to go faster than the Earth in
> > order to escape its gravity. Your car is moving faster than the
> Earth
> > even if it's only going 5mph. The 5mph is IN ADDition to the speed
> of
> > the Earth since your car is moving at Earth speed when standing
> still.
>
> And this is crap, too. The Earth rotates from west to east at 1000
mph
> at the equator. An airplane traveling with ground speed 500 mph will
be
> going 1500 mph with respect to the sun if flying from west to east,
and
> 500 mph with respect to the sun if flying from east to west.
>
> >
Crap? No, I don't think so. You seem to have airplanes confused with
cars, too.
> > >
> > >
> > > Timmy gets hit with the apple and so he picks up a rock and
throws
> it
> > > at me in the moving car and it hits me in the nose with a
relative
> > > velocity of 80 mph.
> > > Now, on the basis of that information, you tell me whether he
threw
> > it
> > > forward (so it's going faster than the car) or backward (so it's
> > going
> > > slower than the car).
> > >
> > He has to throw it faster than the car is moving in order for it to
> > catch up with the car. Whether Tim threw it forward or backward is
> not
> > relevant in this experiment.
>
> And this is still further crap. If Timmy is in front of the car, and
he
> throws it backward at 20 mph, it will hit me in the nose at 80 mph.
If
> Timmy is in back of the car, he will have to throw it 140 mph to have
> it hit me in the nose at 80 mph. Either way is possible and you can't
> distinguish them from the information given.
>
> Tom, you have little to no understanding of relative motion. I could
> give you some practice problems to try to correct that, if you
like...
>
> >
No, thanks, I'll pass on that. You seem to have the wrong notions
about relative motions, I wonder where they came from. I hope that's
not what is being taught in the schools today.

TomGee

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