A simple model of a glider flying along up and down but not left or right (“planar” motion...

A simple model of a glider flying along up and down but not left or right (“planar” motion) is given by

where Ɵ represents the angle of the nose of the glider with the horizon, s > 0 rep resents its speed, and D ≥ 0 is a parameter that represents drag (see the DETools program HMSGlider).

(a) Calculate the equilibrium points for this system.

(b) Give a physical description of the motion of the glider that corresponds to these points.