
On Mon, 27 Mar 2006 23:28:08 +0200, "Paul B. Andersen"
<[email protected]> wrote:
>Henri Wilson wrote:
>> On Wed, 22 Mar 2006 16:42:29 +0100, "Paul B. Andersen"
>> <[email protected]> wrote:
>>
>>>There is but one definition of the centrifugal and Coriolis
>>>pseudo forces in _mechanics_. You can look it up in any text book.
>>>Or you can read my posting.
>>>But OK, let me repeat it.
>>>
>>>In a frame rotating with the angular velocity w (a vector)
>>>we have the following pseudo forces acting on a body with mass m
>>>which is moving with the velocity u (a vector) in the rotating frame:
>>>
>>>The centrifugal force:
>>> F = m* (w X (w X r)) where r is the radius vector.
>>> The magnitude of this force will be m*w^2*r, and
>>> its direction will always be radially outwards.
>>> Expressed with the speed v = w*r : F = m*v^2/r
>>
>>
>> Paul, that is centripetal force. (you omitted the minus sign somewhere)
>>
>> In the rotating frame, w = 0.
>
>I am obviously talking to an idiot.
w is the rotation of the R frame in the nonR frame as measured in the NonR
frame.
The R frame has no rotation in itself.
>> You obviously don't understand the basics.
>
>You reveal an astonishing ignorance of elementary
>Newtonian mechanics, and say that I don't understand the basics.
>How pathetic.
>
>This is obviously futile, you will never learn the basics anyway.
I am trying to teach YOU the basics but you are too thick....
>>> Note that the centrifugal force does NOT depend on
>>> the velocity u in the rotating frame.
>>
>>
>> The imaginary Centrifugal force has the same value as the centripetal force
>> in
>> the nonrotating frame. It's an 'instantaneous' thing.
>>
>>
>>>The Coriolis force:
>>> F = 2*m*(w X u)
>>>
>>> Note that the direction of this force always is
>>> in the plane of rotation, and is perpendicular to
>>> the velocity u. When u is tangential as in our case,
>>> the direction will be radial.
>>
>>
>> But in the case of a rotating sphere, such as Earth, it is NOT always in that
>> plane.
>> You calculation applies to the force due to change in angular momentum in the
>> NonR frame.
>> Coriolis is the imaginary equivalent in the R frame (where w is again zero).
>>
>>
>>>This NG is a sci group.
>>>When you discuss in this group, you better use the normal
>>>accepted definitions of centrifugal and Coriolis,
>>>don't invent your own.
>>
>>
>> Paul, in the R frame, w = 0. Do you disagree with that.
>
>You are an idiot!
>"In a frame rotating with the angular velocity w (a vector).."
....w as measured in the NonR frame, the angular velocity is zero (in ITSELF,
the R frame).
>
>Enough!
Yes you will never learn
Coriolis and centrifugal forces are both imaginary and exist only in rotating
frames.
>
>Paul
HW.
www.users.bigpond.com/hewn/index.htm

