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Topic: Momentum and kinetic energy
Replies: 30   Last Post: Apr 20, 2007 6:42 PM

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briggs@encompasserve.org

Posts: 404
Registered: 12/6/04
Re: Momentum and kinetic energy
Posted: Apr 20, 2007 2:13 PM
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In article <1177082907.476017.156940@n59g2000hsh.googlegroups.com>, Peter <Poakfield@msn.com> writes:
> Only a net force can produce an acceleration, and the acceleration
> must be in the direction of the force. That is what Newton's second
> law says.


Newton's second law applies in inertial frames. "tangential"
isn't a single direction in a single inertial frame.

If you want to stick with a single rotating frame, Newton's laws
can be made to work. But that involves Coriolis pseudo-force.

If you want to use a series of inertial tangent frames, you're not
allowed to frame-jump without a coordinate system transformation.
Choose the frames carefully. If you choose them so that the
transformation does not contribute to tangential velocity then
the "radial" force will have a "tangential" component. If
you choose them so that the "radial" force has no tangential
component then the transformations will convert radial velocity
into tangential velocity. Your assertion fails either way.

If you want to use an inertial frame then "tangential" isn't a
single direction your overly-simplistic application of Newton's
second law is laughably invalid.


Date Subject Author
4/19/07
Read Momentum and kinetic energy
Peter R. Oakfield
4/19/07
Read Re: Momentum and kinetic energy
Vishvas Vasuki
4/19/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/19/07
Read Re: Momentum and kinetic energy
Tony
4/19/07
Read Re: Momentum and kinetic energy
John Morriss
4/19/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/19/07
Read Re: Momentum and kinetic energy
G.E. Ivey
4/19/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/19/07
Read Re: Momentum and kinetic energy
Randy Poe
4/19/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/19/07
Read Re: Momentum and kinetic energy
Randy Poe
4/19/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/19/07
Read Re: Momentum and kinetic energy
Randy Poe
4/19/07
Read Re: Momentum and kinetic energy
Randy Poe
4/20/07
Read Re: Momentum and kinetic energy
briggs@encompasserve.org
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/20/07
Read Re: Momentum and kinetic energy
John Morriss
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/20/07
Read Re: Momentum and kinetic energy
Greg Neill
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/20/07
Read Re: Momentum and kinetic energy
Greg Neill
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/20/07
Read Re: Momentum and kinetic energy
Greg Neill
4/20/07
Read Re: Momentum and kinetic energy
briggs@encompasserve.org
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield
4/20/07
Read Re: Momentum and kinetic energy
Randy Poe
4/20/07
Read Re: Momentum and kinetic energy
John Morriss
4/19/07
Read Re: Momentum and kinetic energy
G.E. Ivey
4/19/07
Read Re: Momentum and kinetic energy
John Morriss
4/20/07
Read Re: Momentum and kinetic energy
Peter R. Oakfield

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