"David CL Francis" wrote in message
...
That is mass you are talking about. I defined weight earlier. But why
'almost' in your world?

That is not mass I'm talking about. It's weight, and the reason it's
"almost" the same as on the ground is that weight depends both on the masses
of the two objects being considered as well as the distance between them.
Weight decreases with the square of the distance.

It is not a 'view' it is definition to help to try and help you
understand the difference between force and mass. I am not the list bit
'tripped up'.

So you say.

The satellite's weight is what keeps it in orbit. It's just not true
that
the satellite weighs zero in orbit. It's my impression that this is what
Jeffrey was saying in his post.

Once more, it is the satellite's MASS that keeps it in orbit and the
MASS of the earth..

The mass only keeps it in orbit inasmuch as mass near another mass causes a
force. This force is weight, and the satellite in orbit has this force
called weight. Without the weight, the satellite would fly off in a
straight line. The acceleration due to weight is the only thing that allows
the satellite to follow a curved path.

[...] However, it is their very
weight that keeps them accelerating toward the planet, as it always does
during the non-parablic phases of flight or even while standing on solid
ground.

You are talking mass again. Weight is a force, Mass is the _quantity_ of
material in an object.

No, I'm talking weight. Mass is not a force. The acceleration toward Earth
is caused by a force. What force? Weight.

For the last time - I am not confused.

Yes, you keep saying that. And yet...

I give up. Get a book on physics or applied mechanics. Perhaps someone
else might be able to help. You seem to be stuck with your preconceived
idea as to what weight and mass are, or to put it another way as to what
a force and a mass are.

So you say. And yet, that's not really the problem here.

If I mention that force is a vector quantity (weight is a force) and
that mass is a scalar quantity, I suppose that will mean nothing to you?

I know the difference between a vector and a scalar. So?

A quote from an A level physics book:
~~~~~~begin quote~~~~~~~~~~
The weight of a body is the force of gravity acting on it towards the
centre of the earth. Weight is thus a _force_ , not to be confused with
mass which is independent of the presence or absence of the earth.
~~~~~~~~~~~~~end quote~~~~~

How does that contradict my statement that the satellite in orbit DOES have
weight? The satellite in orbit is affected by the force of gravity acting
on it towards the center of the Earth. Your quote defines this as "weight".
By your own quote, the satellite DOES have weight.

The Gravitational force F between two particles of masses m1 and m2 , a
distance r apart ,is given by;

F=(G*m1*m2)/r^2 where G is the Gravitational constant.

I am quite aware of that. You'll notice that this gravitational force is
the same as weight. You'll also notice that nowhere in that equation is
there any term that would differentiate between a satellite in orbit and a
satellite sitting motionless at the same distance from the planet. Both
satellites wind up with the same "F", and that "F" is their weight.

So, please...I'd love to hear you try to explain again why it is the
satellite in orbit has no weight.

Pete