We study gaseous outflows from disk galaxies driven by radiation pressure on dust grains .
We include the effect of bulge and dark matter halo and show that the existence of such an outflow implies a maximum value of disk mass-to-light ratio .
We show that the terminal wind speed is proportional to the disk rotation speed in the limit of a cold gaseous outflow , and that in general there is a contribution from the gas sound speed .
Using the mean opacity of dust grains and the evolution of the luminosity of a simple stellar population , we then show that the ratio of the wind terminal speed ( v _ { \infty } ) to the galaxy rotation speed ( v _ { c } ) ranges between 2 \hbox { - - } 3 for a period of \sim 10 Myr after a burst of star formation , after which it rapidly decays .
This result is independent of any free parameter and depends only on the luminosity of the stellar population and on the relation between disk and dark matter halo parameters .
We briefly discuss the possible implications of our results .