A particle of mass `10^(-3)` kg and charge 1.0 c is initially at rest At time t=0 the particle comes under the influence of an electric field `hat (E )(t)=E_(0) sin omega t hat(i)` where `E_(0) =1.0 N C^(-1)` and `omega =10^(3) rad s^(-1)` consider the effect of only the electrical force on the particle .Then the maximum speed in m `s^(-1)` attained by the particle at subsequent times is ______________