Step 1 : Introduction to the question "How fast can droplets fly from our mouths when we cough?"
...When we cough, we first draw a deep breath. A compression of the air in the lungs follows this and then we get a crackling, bursting sound as we force the air out in a fraction of a second. This also forces out thousands of tiny saliva droplets - about 3,000 of them in a single cough. These droplets can fly at speeds up to 50 mph as they fly out of our mouths. Source: LiveScience.com