System of differential equations

*To*: mathgroup at smc.vnet.net*Subject*: [mg128970] System of differential equations*From*: hazem.abdelhafiz at gmail.com*Date*: Thu, 6 Dec 2012 04:58:13 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net

Dear all, I want to solve this system of equations but I always get an error NDSolve::ndnum:Encountered non-numerical value for a derivative at t==0 can any one help me on this s=NDSolve[{ ph1''[t]+ph1'[t]+sin[ph1[t]]-mu[t]-mu'[t]==0.005, ph2''[t]+ph2'[t]+sin[ph2[t]]+mu[t]+mu'[t]==0.005, 0.2mu'[t]+mu[t]==ph1'[t]-ph2'[t], ph2[0]==0, ph1[0]==0, ph2'[0]==0, ph1'[0]==0, mu[0]==0 }, {ph1[t],ph2[t],mu[t]}, {t,0,5000} ] thanks in advance,

**Follow-Ups**:**Re: System of differential equations***From:*Bob Hanlon <hanlonr357@gmail.com>