Theory and observation..
While I was stopped at a red light and taking a drag on a cigarette a curiosity came over me:
When I accelerate, the smoke that left the end of my cigarette does not travel to the rear of the car. More thinking, would an un-tethered balloon, stay pace with my accelerating or float to the rear of the car ?
The smoke that leaves the cigarette, although lighter than air, still at a molecular level attached to the cigarette, if so at which point do smoke particles, isolated or collectively, become independent of the cigarette.
What are the factors?
Working trials and experiments.