how gold gets 4-104
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Short working note by Phil dated 7.24.12, reconstructing Goldstein's derivation of 4-105 in rotating frames. He first translates Goldstein's notation into his own S and S' notation, using cross velocities, then rederives a'S = a'S' + 2 ω x v'S' + ω x (ω x r'). He ends by noting a conflict with his earlier Gold Rule version 8 result, which seems to lack the factor of 2.
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How does Gold get 4-105? PhL 7.24.12
[ Here I realize that Goldstein is using one of the "cross velocities" in his discussion, and this is now all explained in frames doc. ]
First, how does he get (4-104) ? In my notation, here is what he does
(dr'/dt)S = (dr'/dt)S' + ω x r'
or
v'S = v'S' + ω x r'
which with the S↔S' rule would translate into
(dr/dt)s = (dr/dt)r + ω x r
or
vs = vr + ω x r
Therefore we see that he is using
vs = v'S vr = v'S '
Therefore, we find that these are the translation rules (including S↔S')
r' → r v'S → vs v'S' → vr
a'S → as a'S'→ ar
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Start with (4-104)
vs = vr + ω x r r = terrestrial
Apply the G rule to vs
(dvs/dt)s = (dvs/dt)r + ω x vs // agrees with first line of 4-105
Now apply (d/dt)r to 4-104
(dvs/dt)r = (dvr/dt)r + ω x (dr/dt)r = ar + ω x vr ar = (dvr/dt)r
Install this into the previous line to get
(dvs/dt)s = ar + ω x vr + ω x vs
Now use 4-104 in here to get
(dvs/dt)s = ar + ω x vr + ω x [vr + ω x r] as = (dvs/dt)s
as = ar + 2 ω x vr + ω x (ω x r) // agrees with second line of 4-105
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How do I translate this all to my notation? I will try my initial idea 4-104 says for me
vr → (dr'/dt)S' = v'S'
vs → (dr'/dt)S = v'S
The if this is correct, the translation of (4-104) is this
v'S = v'S' + ω x r' r' = terrestrial = frame S'
This is one of my supposedly valid equations which leads me to the idea shown for vr and vs.
Now apply the G rule to v'S = vs
(dv'S/dt)S = (dv'S/dt)S' + ω x v'S // my version of first line of 4-105
Now apply (d/dt)S' to 4-104 assuming ω = constant
v'S = v'S' + ω x r'
(dv'S/dt)S' = (dv'S'/dt)S' + ω x (dr'/dt)S' = a'S' + ω x v'S'
Install this into two lines back to get
(dv'S/dt)S = a'S' + ω x v'S' + ω x v'S
Now in the last term use v'S = v'S' + ω x r' and we then get
(dv'S/dt)S = a'S' + ω x v'S' + ω x v'S' + ω x (ω x r')
which says
a'S = a'S' + 2 ω x v'S' + ω x (ω x r')
and all is well.
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The only problem is that I think I have showed in Gold Rule version 8 that
a'S = a'S' + ω x v'S (7.2)
and then this becomes, using 6 lines above,
a'S = a'S' + ω x v'S' + ω x (ω x r')
and this just does not look the same! as 3 lines above!!! I am then missing the factor of 2 !