What effect do collisions among planetesimals of greatly varying size have on the formation of planets?

Short, sweet and surreal ... I imag/conject that the initial mass of gas and dust is rotating and the particles are small ... accretion between particles wud b due 2 electrostatic attraction (lot of radiation flying about) ... when some of the particles get macroscopic then u wud get grav forces ... ie if the rel vel between 2 'macro-particles'< escape vel ... u get coalescence and a bigger particle ... on the other hand this process must be in equilibrium with the situation where the actual impact vel fragments the particles

The small ones get to be "swallowed up" by using the bigger ones, due to gravity. finally, the planetesimals can become planets with the aid of this procedure, which called "accretion". Planetesimals are solid objects conceptto exist in protoplanetary disks and in debris disks.