Oops, I meant to write $B!H(B faster $B!I(B, not $B!H(B higher $B!I(B:
$B!H(B If the earth's orbit around the sun happened to be slightly faster
it'd be Spiraling Away From the sun ( a bit more each year );
conversely, it'd be spiraling Into the sun. $B!I(B.

"Richo" <m.richardso...@gmail.com> wrote in message

news:f05a1961-d338-4635-9f3c-5d39d261bf03@f24g2000prh.googlegroups.com...



On Apr 29, 10:54 am, "Mark Earnest" <gmearn...@yahoo.com> wrote:
"Richo" <m.richardso...@gmail.com> wrote in message

news:a6e91e59-7622-4f1b-b262-a5725bcded36@n1g2000prb.googlegroups.com...

On Apr 28, 1:15 pm, "Mark Earnest" <gmearn...@yahoo.com> wrote:
"Sam Wormley" <sworml...@mchsi.com> wrote in message

news:jdaRj.139437$yE1.67749@attbi_s21...

Mark Earnest wrote:
The Earth does not fall into the Sun because it is constantly
accelerating
at a right angle to the Sun.

Whoops! The force (gravity) is directed toward the sun and hence
the
acceleration is directed toward the sun.

Whoops yourself. If the acceleration was all toward the Sun, the
planet
would fall into the Sun, just as the OP perceives.

The Earth does fall towards the center of the sun - continuously.
It has been falling towards the center of the sun for 4.5 billion
years now.
It never gets any closer because of its tangential velocity - earths
momentum wants to move the earth in a straight line - the acceleration
of gravity pulls it off course constantly and makes the earth move in
a circle (an ellipse really but lets keep it simple).
If gods hand reached down and stopped the earths motion - and then let
go the earth would slowly move towards the center of the sun getting
faster and faster - if gods hand reached down and gave the earth a
sideways push - it would fall into orbit.
The orbit is the place where the tangential motion is exactly balanced
by the inward acceleration.

It is the right angel acceleration that keeps the planet from falling
into
the Sun.

Not acceleration - constant speed - momentum.

It has to be acceleration, otherwise there is no ballance for the
accelerating force of gravity from the Sun.

The suns gravity pulls the earth towards it - what pulls the earth
"sideways"?

Same sort of thing that is pulling you down at this very moment.
An unexplained force.

There is no such force - there is momentum and there is the force of
gravity.
Together they guarantee that the planets orbit in an ellipse.

Satelites orbit the earth without having to constantly fire their
rockets.
If they do fire their rockets to increase their tangential velocity
they go into a higher orbit.

If something pushed the earth sideways it would move into a higher
orbit.
If something retarded its sideways motion it would fall to a lower
orbit.
If there is Zero sideways acceleration - it will orbit at the same
distance from the Sun forever.

Any change in velocity is an acceleration - if you draw the vectors
the *change* in velocity is directed towards the center of the circle.
the *change* in velocity in the tangential direction is zero, none.

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

If God's hand really were in this--and it could be--and he mysteriously
somehow made the Sun wink out of existence, The Earth would continue in
the
same line it was in at the disappearance, but would continue to
accelerate...and accelerate...and accelerate...until it reached the
fastests
of all possible velocities.

No - to accelerate it needs a force - there is no tangential force -
if the sun winked out of existence the earth would continue on at a
constant velocity.

To accelerate down to the Earth requires no force.

Just the same way, an object sufficiently accelerated in space will need
no such force. It is just the way things behave in space.

The way things behave in space is "to continue in a uniform state of

We will have to do some exploring and a little philosophizing to decide what
is pulling planets in an acceleration around their respective stars.

We have yet to explain gravity.

So what of it?

Please don't argue with this - I am not trying to fool you - I am not
lying.
I am trying to teach you something - for free!
(I do have a degree in physics by the way - normally I would charge
for tuition)

I respect your education. I took the first year of physics and made an A.
But I found too many unexplained phenomena in physics and decided to
go after reality in my own way.

You just need to think carefully about the fact that acceleration
needs a force - staying at a constant velocity is just momentum.

I think you can do this Mark - i have faith ! - just think about that
rock on a string whirling about your head - the only two things going
on are a central force (acceleration inwards) and momentum.

A planet going around the Sun is hardly a rock on a tether.

The planet is going by its own propulsion, while a rock is going
by the swaying propulsion of the person on the other end of the tether.

When Sun and Earth are attracting each other why do Earth not fall on
Sun.

When we throw a big Stone in air It will Fall Back on Earth.
Simmilarly For Sun Earth is just a piece of Rock? Who do this big rock
Earth Fall onto the Sun Just like the Stones which we throw in air
just come back and hit the Earth?

Simmilarly why not the Moon fall on Earth by the Gravity attration?

Why are the planets revolving round the sun for so many years instead
of just falling onto the Sun?

When we visit Moon on a Rocket Our Rocket Just Falls on Surface of
moon So why these heavenly bodies not falling on Bigger one?

Bye
Sanny

Extreme Discussions at:http://www.getclub.com/Discussion.php

As you noted, I was wrong, so:
simple orbits don't spiral Away From or Into the sun.

But, 16.5 hours ago, I made the same apology to Michael Moroney:

And, 14.5 hours ago, I made the same apology to Saul Levy:

Seeing as ( almost ) no one reads anything but direct replies
( if that ), I'll keep repeating myself over and over again.

flamestar wrote:
Not true the earth does not have an elliptical orbit because it
wobbles in its orbit. You are a person who so hates the truth that you
seek to prevent people from understanding scientific principles by
bring up irrelevant details. The world is an evil place because you
are in it.

In any case the earth orbit is not circular.

Bob Kolker

Sanny wrote:
When Sun and Earth are attracting each other why do Earth not fall on
Sun.


When we throw a big Stone in air It will Fall Back on Earth.
Simmilarly For Sun Earth is just a piece of Rock? Who do this big rock
Earth Fall onto the Sun Just like the Stones which we throw in air
just come back and hit the Earth?

Simmilarly why not the Moon fall on Earth b y the Gravity attration?

Why are the planets revolving round the sun for so many years instead
of just falling onto the Sun?

When we visit Moon on a Rocket Our Rocket Just Falls on Surface of
moon So why these heavenly bodies not falling on Bigger one?

Bye
Sanny

On Apr 27, 3:53 am, Sanny <softta...@hotmail.com> wrote:
When Sun and Earth are attracting each other why do Earth not fall on
Sun.

When we throw a big Stone in air It will Fall Back on Earth.
Simmilarly For Sun Earth is just a piece of Rock? Who do this big rock
Earth Fall onto the Sun Just like the Stones which we throw in air
just come back and hit the Earth?

Simmilarly why not the Moon fall on Earth by the Gravity attration?

Why are the planets revolving round the sun for so many years instead
of just falling onto the Sun?

When we visit Moon on a Rocket Our Rocket Just Falls on Surface of
moon So why these heavenly bodies not falling on Bigger one?

Bye
Sanny

Extreme Discussions at:http://www.getclub.com/Discussion.php

This is a deep question. It goes right to the heart of why gravity
and space behave the way they do. As posted above, Newton and
Einstein have given us mathematical models of *how* gravity and space
behave but not *why*. The only answer that comes to mind is the
anthromorphic principle, which seems to me to be not quite satisfying.

In article
91fc07f0-5c11-4056-a817-bbb10ff28f61@j33g2000pri.googlegroups.com>,
Sanny <softtanks@hotmail.com> wrote:

When Sun and Earth are attracting each other why do Earth not fall on
Sun.


When we throw a big Stone in air It will Fall Back on Earth.

When you throw a stone horizontally, why doesn't it fall straight down
(doesn't gravity pull it down)?
What if you threw the stone faster? What would it do?
What if you could throw the stone much, much faster?

Didn't you learn this in high school?

On Apr 27, 10:22 am, "Robert J. Kolker" <bobkol...@comcast.net> wrote:
flamestar wrote:
The answer is as both A and B are right they split the difference and
the Earth does not move away from the sun or fall into it. It stays
the same distance away.

Not true.
The earth has an eliptical orbit.
Bob Kolker


Not true the earth does not have an elliptical orbit because it
wobbles in its orbit. You are a person who so hates the truth that you
seek to prevent people from understanding scientific principles by
bring up irrelevant details. The world is an evil place because you
are in it.

On Apr 30, 12:46 pm, "Mark Earnest" <gmearn...@yahoo.com> wrote:
"Richo" <m.richardso...@gmail.com> wrote in message

news:f05a1961-d338-4635-9f3c-5d39d261bf03@f24g2000prh.googlegroups.com...



On Apr 29, 10:54 am, "Mark Earnest" <gmearn...@yahoo.com> wrote:
"Richo" <m.richardso...@gmail.com> wrote in message

news:a6e91e59-7622-4f1b-b262-a5725bcded36@n1g2000prb.googlegroups.com...

On Apr 28, 1:15 pm, "Mark Earnest" <gmearn...@yahoo.com> wrote:
"Sam Wormley" <sworml...@mchsi.com> wrote in message

news:jdaRj.139437$yE1.67749@attbi_s21...

Mark Earnest wrote:
The Earth does not fall into the Sun because it is constantly
accelerating
at a right angle to the Sun.

Whoops! The force (gravity) is directed toward the sun and
hence
the
acceleration is directed toward the sun.

Whoops yourself. If the acceleration was all toward the Sun, the
planet
would fall into the Sun, just as the OP perceives.

The Earth does fall towards the center of the sun - continuously.
It has been falling towards the center of the sun for 4.5 billion
years now.
It never gets any closer because of its tangential velocity - earths
momentum wants to move the earth in a straight line - the
acceleration
of gravity pulls it off course constantly and makes the earth move
in
a circle (an ellipse really but lets keep it simple).
If gods hand reached down and stopped the earths motion - and then
let
go the earth would slowly move towards the center of the sun getting
faster and faster - if gods hand reached down and gave the earth a
sideways push - it would fall into orbit.
The orbit is the place where the tangential motion is exactly
balanced
by the inward acceleration.

It is the right angel acceleration that keeps the planet from
falling
into
the Sun.

Not acceleration - constant speed - momentum.

It has to be acceleration, otherwise there is no ballance for the
accelerating force of gravity from the Sun.

The suns gravity pulls the earth towards it - what pulls the earth
"sideways"?

Same sort of thing that is pulling you down at this very moment.
An unexplained force.


Gravity is unexplained - fine - but I can observe it - I can measure
it.
I know how to describe it mathematically F =G m1 m2 / r^2

The force you are talking about is not only not explained it is not
observed.

There is no such force - there is momentum and there is the force of
gravity.
Together they guarantee that the planets orbit in an ellipse.

Satelites orbit the earth without having to constantly fire their
rockets.
If they do fire their rockets to increase their tangential velocity
they go into a higher orbit.

If something pushed the earth sideways it would move into a higher
orbit.
If something retarded its sideways motion it would fall to a lower
orbit.
If there is Zero sideways acceleration - it will orbit at the same
distance from the Sun forever.

Any change in velocity is an acceleration - if you draw the vectors
the *change* in velocity is directed towards the center of the circle.
the *change* in velocity in the tangential direction is zero, none.

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

If God's hand really were in this--and it could be--and he
mysteriously
somehow made the Sun wink out of existence, The Earth would continue
in
the
same line it was in at the disappearance, but would continue to
accelerate...and accelerate...and accelerate...until it reached the
fastests
of all possible velocities.

No - to accelerate it needs a force - there is no tangential force -
if the sun winked out of existence the earth would continue on at a
constant velocity.

To accelerate down to the Earth requires no force.

Yes it does it requires gravity.
When you weigh a sack of potatoes it is the force of gravity that
pushes the potatoes down on the scale.

Just the same way, an object sufficiently accelerated in space will need
no such force. It is just the way things behave in space.

The way things behave in space is "to continue in a uniform state of
motion unless acted upon by a force" - Newtons first law.

We will have to do some exploring and a little philosophizing to decide
what
is pulling planets in an acceleration around their respective stars.

We have yet to explain gravity.

So what of it?


You don't need to explain gravity - you can observe it, measure it and
quantify it as precisely as you like.


Please don't argue with this - I am not trying to fool you - I am not
lying.
I am trying to teach you something - for free!
(I do have a degree in physics by the way - normally I would charge
for tuition)

I respect your education. I took the first year of physics and made an
A.
But I found too many unexplained phenomena in physics and decided to
go after reality in my own way.


Whatever way you come up with it cant be true AND contradict other
true things.
The stuff i am telling you has been known to be true since Issac
Newton - one of the most brilliant humans ever to have lived.
A bit of a religious nutter too - but still a true genius.

You just need to think carefully about the fact that acceleration
needs a force - staying at a constant velocity is just momentum.

I think you can do this Mark - i have faith ! - just think about that
rock on a string whirling about your head - the only two things going
on are a central force (acceleration inwards) and momentum.

A planet going around the Sun is hardly a rock on a tether.

It is exactly like a rock on a tether - except for wind resistance.

If you did the rock on a tether while floating outside the Space
Station THEN it would be exactly the same.
The astronaut could get the rock whizzing, tie the end of to a pole
and go away - it would still be whizzing a week or a month later -
because there would be no energy lost to wind resistance.

The planet is going by its own propulsion, while a rock is going
by the swaying propulsion of the person on the other end of the tether.

The only reason you have to give the rock little swaying accelerations
is to counter the loss of energy from wind resistance.

A planet *has* no propulsion - there is no rocket motor pushing the
earth around in its orbit - its just inertia and falling towards the
center of the sun - falling forever.

An artificial satellite doesn't need to fire its engines to remain in
orbit - once it is in orbit it can stay there essentially forever - it
continuously falls towards the center of the earth and moves under its
own momentum.

Cheers, Mark.

You don't need to explain gravity to observe it, do you?
And it is observed if you understand the descrepancy
in the modern understanding of orbital mechanics.

Mark Earnest wrote:


You don't need to explain gravity to observe it, do you?
And it is observed if you understand the descrepancy
in the modern understanding of orbital mechanics.


Mark... from these postings it is clear that you have some
misunderstandings of simple mechanics... the relationships
between displacement, velocity, acceleration, gravitation,
including the mechanics of trajectories and, yes, orbital
motion.

I don't point this out as a put down, but trying to let you
know that you would benefit by going over the first half
dozen chapters of a textbook like Halliday and Resnick...
working the problems so you know you've got it!

This newsgroup (sci.physics) can be very helpful for those
working on homework problems and assisting with real
understanding. An excellent opportunity.

Regards,
-Sam

From Wikipedia "In physics and cosmology, the anthropic principle
states that humans should take into account the constraints that human
existence as observers imposes on the sort of universe that could be
observed. In other words, the only universe we can see is one that
supports life. If it were a different type of universe, we would not
exist to see it."

Recommend you get yourself a freshman physics book and do
some self education. Best of luck.

I've already taken that class and made an A.