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From: Liater on 16 Feb 2010 10:10
v


From: xxein on 16 Feb 2010 18:46
On Feb 16, 11:50 am, John Duffield <johnduffi...(a)btconnect.com> wrote:
> Yes, there is a force of gravity. But it isn't the same kind of force
> as when you push an object to make it move. In the latter situation
> you are transferring energy to the object. Gravity doesn't do this.
> Instead it converts potential energy into kinetic energy, and is
> sometimes called an "internal force" as opposed to an "external
> force". It's also sometimes called a "pseudoforce", but definitions
> can be ambiguous and the subject of debate.

xxein: Now, what kind of 'force' does the seeking of an equilibrium
induce?
From: valls on 17 Feb 2010 06:43
On 16 feb, 11:50, John Duffield <johnduffi...(a)btconnect.com> wrote:
> Yes, there is a force of gravity. But it isn't the same kind of force
> as when you push an object to make it move. In the latter situation
> you are transferring energy to the object. Gravity doesn't do this.
> Instead it converts potential energy into kinetic energy, and is
> sometimes called an "internal force" as opposed to an "external
> force". It's also sometimes called a "pseudoforce", but definitions
> can be ambiguous and the subject of debate.
And what about the electric force between two charged entities? It is
also a "pseudoforce"?

RVHG (Rafael Valls Hidalgo-Gato)
From: John Duffield on 16 Mar 2010 11:08
xxein:  Now, what kind of 'force' does the seeking of an equilibrium
induce?

The transfer of energy from one part of a system to another. For
example the kinetic energy of a mass is transferred into the potential
energy in a spring, which then pushes back. There are no springs in
gravity. Throw an object upwards, and the energy you gave it doesn't
leave that object.

From: John Duffield on 16 Mar 2010 11:14

> RVHG: And what about the electric force between two charged entities? It is also a "pseudoforce"

I wouldn't call it that myself. But if you've got a system consisting
of an electron and a positron accelerating towards one another,
conservation of energy tells you they can't give each other more
energy.

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