A particle, of mass $10^{-3} \mathrm{~kg}$ and charge 1.0 C , is initially at rest. At time $\mathrm{t}=0$, the particle comes under the influence of an electric field $\overrightarrow{\mathrm{E}}(\mathrm{t})=\mathrm{E}_0 \sin \omega \mathrm{t} \hat{\mathrm{i}}$, where $\mathrm{E}_0=1.0 \mathrm{NC}^{-1}$ and $\omega=10^3 \mathrm{rad} \mathrm{s}^{-1}$. Consider the effect of only the electrical force on the particle. Then the maximum speed, in $\mathrm{m} \mathrm{s}^{-1}$, attained by the particle at subsequent times is $\_\_\_\_$ .