How big is a drop..

[XperienceMe]

of water from lets say a visine eye dropper in ml on avrage?

 

[Pomzazed]

If it's water it should be around 1/20 of a mL. This is a very roughtly avergage as it can differs quite alot (1/15~1/30 of mL)

Each liquid varies depending on the viscosity.

 

[Carsick]

Good question.
Purely based on experience with a couple of different droppers, it's something like 0.02ml. That's from how many drops I got out of a known amount of liquid.
Of course, some were much larger, and some would logically have been smaller. It's not an easy thing to do accurately.

 

[johanneschimpo]

To be safe, don't use "drops" as a unit of measurement, at least until your dropper is calibrated and you know the exact size of your drops.

 

[vecktor]

perhaps UTFSE

http://www.bluelight.ru/vb/showthread.php?t=316364

 

[fastandbulbous]

Same as 'how long is a piece of string' - too many variables (size of hole, shape of dropper, viscosity of liquid...)

If you want a definitive figure, draw up 1ml accurately measured (a 1ml syringe should suffice), squirt the complete 1ml into the dropper then count how many drops you get from that 1ml. The volume of a drop is then = (1/no of drops)ml

For water and your standard sort of dropper obtainable at health food stores, pharmacies etc., you're looking at 0.02ml - 0.05ml per drop