Rotational transform: Difference between revisions
→Safety factor
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<ref>K. Miyamoto, ''Plasma Physics and Controlled Nuclear Fusion'', Springer-Verlag (2005) ISBN 3540242171</ref> | <ref>K. Miyamoto, ''Plasma Physics and Controlled Nuclear Fusion'', Springer-Verlag (2005) ISBN 3540242171</ref> | ||
:<math>\frac{r d\theta}{B_\theta} = \frac{Rd\ | :<math>\frac{r d\theta}{B_\theta} = \frac{Rd\varphi}{B_\phi}</math> | ||
where ''& | where ''ϕ'' and ''θ'' are the [[Toroidal coordinates|toroidal and poloidal angles]], respectively. | ||
Thus ''q = m/n = <d& | Thus ''q = m/n = <dϕ/dθ>'' can be approximated by | ||
:<math>q \simeq \frac{r B_\ | :<math>q \simeq \frac{r B_\varphi}{R B_\theta}</math> | ||
== See also == | == See also == | ||