Low Gravity and Its effects on fluids

[Mav359]

Hi

I need cleverer minds than my own...... i have a question regarding the effect of low gravity and fluids

We have all seen astronauts in space and the effects zero-g has on water but how low does gravity have to get before it does that?

If we could land on a planet with only 0.2g of earth would the coffee in you mug float away with a knock or does fluid remain grounded until theres no gravity at all. How low can it get before its beyond using a glass or mug?

Cheers

 

[Catastrophe]

I cannot answer all your question, but I will try to start.

There are two effects here. One is the cohesion of liquid molecules floating in the air. The fact that you can see them shows that there is sufficient gravitational force to hold them together, albeit loosely.
Second factor is, in addition to this cohesion, do they start in a cup or vessel. If, in low gravity, they are poured into the cup (carefully) they may stay there providing the gravity is sufficient to hold them. I guess we can consider liquid molecules (at least low molecular weight liquids - not mercury) under very low gravity as similar to Brownian movement in gases. I am sure someone more knowledgeable than I will be quick to correct me. This would come down to be dependant on the level of gravity, but also on the size (mass) of the individual liquids concerned. Thus there is (IMHO) no simple single solution. I guess no one is surprised at that.

Does that do for a start, in defining some parameters?

Cat