Answer:
cloud contain water vapor which is form of small condense water droplet
when fall velocity exceed cloud up draft speed
Explanation:
we know that cloud contain water vapor which is form of small condense water droplet
but some time cloud water droplet not fall as rain even they are condensed water because their speed of falling not enough to overcome updraft that support to the cloud
as small water drop condense on tiny dust particle, smoke particle or salt particle
when enough collision are happen to produce water drop which is fall velocity exceed cloud up draft speed
then it will fall out