I recently read about the size of raindrops, and they can be as small as a few hundredths of an inch in diameter. How is such small size measured? How is it done?
Droplet size is what separates drizzle from rain, and the threshold is two hundredths of an inch, or 1/50 inch in diameter. Drizzle lies as the smaller end of the scale and rain at the larger end.
Measuring raindrops these days is a high-tech matter. Researchers employ a variety of techniques: high-speed photographs of falling drops, microscopic photography of tiny drizzle droplets (and even smaller fog droplets), specially designed “raindrop radars” and electric sensors that determine the force of the impact of a drop on a metal sheet (larger drops hit harder).