- #1
physnoct
I want to demonstrate to flat earthers that water does indeed stick to a ball. If we want to do a scale model of the earth, at which radius will gravity overcome the surface tension?
physnoct said:I want to demonstrate to flat earthers...
physnoct said:I want to demonstrate to flat earthers that water does indeed stick to a ball. If we want to do a scale model of the earth, at which radius will gravity overcome the surface tension?
For FEers, maybe. The question itself is worth an answer, as it is an interesting physics challenge and I would like to know the answer.CWatters said:That would be a waste of time.
That's a good start! I'll check that. Thanks!Andy Resnick said:The Bond number (Eotvos number) is the ratio of gravitational and interfacial energies: when the Bond number is high, gravity dominates and vice-versa. So all you need to do is write down the Bond number for your scale model and determine what the critical value of 'planetary' mass is (when Bo = 1)
Is there a formula that I can use?CWatters said:Put a drinking straw into a glass of water and the water will rise up the straw until gravity "overcomes" surface tension.
Surface tension is the force that causes the molecules on the surface of a liquid to stick together, creating a layer of tension that keeps the liquid from spreading out.
Objects on the surface of a liquid experience surface tension as an upward force, known as surface tension force. This force is what allows insects, such as water striders, to walk on water.
Gravity takes over surface tension when the weight of an object on the surface of a liquid becomes greater than the surface tension force. This typically occurs with larger, heavier objects or with objects that are submerged deeper into the liquid.
When gravity takes over surface tension, the object on the surface of the liquid will sink. This is because the force of gravity is stronger than the force of surface tension, causing the object to break through the surface and sink into the liquid.
The shape of an object can greatly affect the balance between surface tension and gravity. Objects with larger surface areas will experience more surface tension force, while objects with smaller surface areas will experience less. Additionally, objects with a more streamlined shape may be able to distribute their weight more evenly on the surface of the liquid, allowing them to stay afloat even with greater gravitational force.