Forced inclination
= Forced inclination
{title2=$w_f$}
The particular, forced part of a <complex inclination> solution. For a fixed, circular, inclined inner <planet> and an exterior test ring, linear <Laplace-Lagrange secular theory> gives $\dot w=-i\nu(w-w_p)$, so $w_f=w_p$ and $w=w_p+(w(0)-w_p)e^{-i\nu t}$. The ring describes a circle about the planetary tilt in an <Argand diagram>; relative to the planet, its <mutual inclination> stays constant while its <ascending node> precesses.