MOTIONVARIABLES' Q{2}'' CONSTANTS L,M,G NEWTONIAN N POINT PN V_PN_N> = 0> THETA1 = ATAN(Q2/Q1) FRAMES A SIMPROT(N, A, 3, THETA1) PARTICLES P P_PN_P> = Q1*N1>+Q2*N2> MASS P=M V_P_N>=DT(P_P_PN>, N) F_V = DOT(EXPRESS(V_P_N>,A), A1>) GRAVITY(G*N1>) DEPENDENT[1] = F_V CONSTRAIN(DEPENDENT[Q1']) ZERO=FR()+FRSTAR() F_C = MAG(P_P_PN>)-L CONFIG[1]=F_C ZERO[2]=CONFIG[1]