Why are your hands slippery when dry, get “grippy” when they get a little bit wet, then slippery again if very wet?
In: Physics
Water sticks to water, making wet things stick to wet things. If the layer of water is thick the surfaces can easilly slide because water easilly slides across itself.
However, if the water layer is thin and the surfaces aren’t smooth then the surfaces can still touch in a lot of places. The water can still stick the surfaces together, but not be thick enough to make sliding easy, and the sticking caused by being wet makes sliding even harder than if the surfaces were dry.
A little bit of water (like licking your fingers to open a plastic produce bag) can help with grip in some circumstances but not all–this is why, for example, athletes sometimes use chalk bags.
If you’re talking about circumstances like opening a produce bag, then it’s more to do with surface tension than with any potential softening of the skin layer, I believe.
If your hands are slippery when dry, your hands are either dirty or you’re dehydrated. Hands are naturally quite grippy, of properly hydrated.
Your body needs moisture to work properly. So the grip of your hands is kind of determined by all the ridges, and their ability to sell swell and squish. All those little lines, like your fingerprints and such, they fill with water when there’s moisture, and then when you grab things, they are able to apply extra pressure, creating better grip. Obviously this swelling is near microscopic, but have you ever stayed in the water until your hands prune? That is your skin swelling to give you grip in such a wet environment.
I’m using this to train for teaching my kids, hope this is good.
Latest Answers