  We study semiflows generated via impulsive perturbations of Lorenz flows. We
prove that such semiflows admit a finite number of physical measures. Moreover,
if the impulsive perturbation is small enough, we show that the physical
measures of the semiflows are close, in the weak* topology, to the unique
physical measure of the Lorenz flow. A similar conclusion holds for the
entropies associated with the physical measures.
