The momentum equations of moving strings are derived by considering the effects of velocity of moving strings. Applying the equations in the analysis of the stable moving of strings, the equation of velocity versus initial angle and bifurcate condition are obtained, the possible curves for moving strings are derived. This paper points out the possible unstable phenomenon of moving strings and the approaches to improve the stability. According to the curve of velocity versus initial angle and the bifurcate condition for moving strings, stably moving can be realized by increasing initial axial f...
