How does ink in a pen refill not fall out and how come when submerged water does not enter the refill?

Answer 1

Capillary action, & viscosity.

Answer 2

Air pressure. Ink is also quite viscus (it flows slowly). There isn't enough room in the refill opening to get both a stream of ink going out, and a stream of air to go in and take its place. Try filling a sealed bottle with water and poking a pin hole in the side. The water won't come out that hole either.

Answer 3

This is a good basic science question. Have you ever filled a glass full of water to the point that the level of the water is slightly ABOVE the rim of the glass? If not, try it.
The answer is called "surface tension". It means that the liquid has such a strong cohesion for itself that it can rise above the rim of the glass without pouring over. (Of course, if you pour even a slight bit more, it will overflow. Surface tension is strong, but has its limits.)
Another example is the case of "magicians" placing a needle carefully on the surface of water in a shallow dish. If done just right, the needle will "float", held up by surface tension.
"Capillary action" is how plants can "drink" water. It is capillary action that moves water up the roots to the stem (or trunk), up through the branches to the leaves.

Please see: http://en.wikipedia.org/wiki/Surface_tension
or: http://www.ilpi.com/genchem/demo/tension/
and for capillary action: http://www.madsci.org/posts/archives/1998-02/887637827.Ch.r.html

Answer 4

You have too much time on your hands. Ink will not 'fall' out, but it can seep out if you partially block the hole. And if submersed in water, it WILL eventually seep into the ink if the refill has an open end. With sealed refills, well, obviously sealed.

Answer 5

I hope you are serious. Its the viscosity of course, coupled with surface tension and skin friction.

Answer 6

what