Section 10 rewrite
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A draft section from Phil's "new frames doc" comparing his swap and non-swap notations with Goldstein (1950) and Goldstein, Poole and Safko (2001). It works through the acceleration equation with Euler, Coriolis and centripetal terms for Special Case #1, where the rotation axis passes through the inertial origin. It looks at whether short versus long position vectors make the equations compatible, and ends with a table mapping his symbols to Goldstein's.
AI-written summary; may contain errors.
Extracted text (machine-read; may contain errors)
10. Notation comparison with Goldstein (1950) and Goldstein, Poole and Safko (2001)
In this Section compare our notation for rotating-frame kinematics and non-inertial-frame physics to that of Goldstein on (1950) and Goldstein, Poole and Safko (GFS 2001).
Their notation seems to assume the Special Case #1 situation where the rotation axis passes through the inertal frame origin, as for rotating-Earth problems.
ATTEMPT USING MY SWAP NOTATION
Recall our two equations in swap notation.
a' = a + x r + 2 ω x v + ω x (ω x r) + S' S = rotating frame (7.6a)s
S' S Euler Coriolis centripetal frame ( r = short vector, r' = long vector)
S' = x b + ω x (ω x b) . // Special Case #1 (7.13)s
Inserting the second into the first and using r' = b+r gives
a' = a + x r' + 2 ω x v + ω x (ω x r') // r' = long vector (*)
We may compare this to the Goldstein equation,
as = ar + x r + 2 ω x vr + ω x (ω x r) . // Goldstein p 135 (4-105) (**)
// GPS p 175 (4.89)
In my equation (*) I have r' = long vector. But in (**) I know that r is a short vector because he says this on page 135. This means that (*) and (**) are not compatible.
Meanwhile, let's compare these two items
vS' = v + ω x r . r = short vector (6.5)s
vs = vr + ω x r . r = short vector // Goldstein p 135 (4-104)
// GPS p 175 (4.88)
I am OK with v = vr in the rotating frame. And r looks right. But in my equation I have
vS' = (dr/dt)S' = (dr/dt)space
I refer to this as a cross velocity because I am looking at the motion of the short vector r in the rotating frame using a time derivative from the space frame. That is certainly OK to do. With this connection that we have vs = vS', we are 100% OK here, which favors this approach.
Maybe he does the same thing with acceleration. He would have
as = ∂S'vS'= ∂2S'r = (∂2r/dt2)space exactly what G says!
So I want then to connect as = aS'S' = aS' . What do I know about this accel?
a'S = a' + x r' + 2 ω x v' + ω x (ω x r') . (7.4)
aS' = a + x r + 2 ω x v + ω x (ω x r) . (7.4)s
Compare this then to
as = ar + x r + 2 ω x vr + ω x (ω x r) . // Goldstein p 135 (4-105) (**)
// GPS p 175 (4.89)
ATTEMPT USING MY NON-SWAP NOTATION
a = a' + x r' + 2 ω x v' + ω x (ω x r') + S S' = rotating frame (7.6a)
S S' Euler Coriolis centripetal frame ( r' = short vector, r = long vector)
S = x b + ω x (ω x b) . // Special Case #1 (7.13)
Inserting the second into the first and using r = b+r' gives
a = a' + x r + 2 ω x v' + ω x (ω x r) . (*) (10.1)
This may be compared with the Goldstein equation (to which we have added a x r term)
as = ar + x r + 2 ω x vr + ω x (ω x r) . // Goldstein p 135 (4-105) (**)
// GPS p 175 (4.89)
In my equation (*) I have r= long vector. But in (**) I know that r is a short vector because he says this on page 135. This means that (*) and (**) are not compatible.
I am unable to find a way to compare the two notations!!
Meanwhile, let's compare these two items
v'S = v' + ω x r' . (6.5)
vs = vr + ω x r . // Goldstein p 135 (4-104)
// GPS p 175 (4.88)
vs = vr + ω x r . // Goldstein p 135 (4-104)
// GPS p 175 (4.88)
All my equations above in swap-notation are these
( r = short vector, r' = long vector)
a' = a + x r + 2 ω x v + ω x (ω x r) + S' S = rotating frame (7.6a)s
S' S Euler Coriolis centripetal frame
S' = x b + ω x (ω x b) . // Special Case #1 (7.13)s
Inserting the second into the first and using r' = b+r gives
a' = a + x r' + 2 ω x v + ω x (ω x r')
Now compare this to
as = ar + x r + 2 ω x vr + ω x (ω x r) . // Goldstein p 135 (4-105)
// GPS p 175 (4.89)
So this is IT!!
our swap Goldstein
notation authors
S r name of the rotating frame
S' s name of the fixed frame (s = space)
∂S' (d/dt)s time derivative in the fixed frame
∂S (d/dt)r time derivative in the rotating frame
r position in rotating frame (short vector)
v vr velocity in rotating frame
a ar acceleration in rotating frame
r' r position in fixed frame (long vector)
v' vf velocity in fixed frame
a' as acceleration in fixed frame
F' F force in fixed frame = true force in rotating frame
Feff Feff total effective force in the rotating frame
Ffict total fictitious force in the rotating frame
b R location of the rotating frame origin (measured in the fixed frame)
S' f,V velocity of the rotating frame origin (measured in the fixed frame)
S' f acceleration of the rotating frame origin (measured in the fixed frame)