Will it float or will it crunch?

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In summary, the conversation discusses the possibility of creating a structure that can float in the atmosphere by removing all trapped air. It is suggested that building a vacuum balloon with a spherical support from a space frame may be a viable option. However, it is noted that this would require two different materials for the support and the outer cover. Overall, it is unlikely that an empty container can float without crushing, and it is more feasible for a spherical shape to float due to the tension in the membrane.
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An oil drum will crunch if all matter is taken out. If you empty an oil drum at the edge of space, ceal it, and release it (without kinetic energy so no escape velocity), wil it float somewhere in the atmosphere? Or will it crunch and fall on the earth? Is it possible to create a stucture strong enough and light enough that when all trapped air is sucked out, will start to float instead of crunch?
 
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Welcome to PF.

The density of air at 15°C and Sea Level is 1.225 kg/m2.
An oil drum has a volume of 200 litres, so to float it would have to weigh less than 1.225 * ( 200 / 1000 ) = 245 gram.
It is unlikely that you could make a drum that would float without crushing. It is far more probable that an empty container that floats in air would be a sphere.

A soap bubble has tension in the membrane so it is stable. Compression in the surface of a very thin shell will result in buckling and collapse if any asymmetric forces are applied.

To build a vacuum balloon you will need to fabricate a spherical support from a space frame having thickness, such as an octet truss. Then collapse the external membrane onto that support. The outer cover should not be in tension until the balloon is evacuated as that would subject the truss to an unnecessary compressive force. That will require two quite different materials for the truss and the skin.

https://en.wikipedia.org/wiki/Geodesic_dome
https://en.wikipedia.org/wiki/Space_frame
 
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Not quite what you asked about but perhaps of interest..

 
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1. Will the object float or sink?

The answer to this question depends on the density of the object and the density of the liquid it is placed in. If the object is less dense than the liquid, it will float. If it is more dense, it will sink.

2. How do you determine the density of an object?

The density of an object can be found by dividing its mass by its volume. Mass is usually measured in grams and volume in cubic centimeters or milliliters. The resulting unit for density is grams per cubic centimeter (g/cm3) or grams per milliliter (g/mL).

3. What is the difference between buoyancy and density?

Buoyancy refers to the upward force that a liquid exerts on an object placed in it. It is dependent on the density of the liquid and the volume of the object. Density, on the other hand, is a measure of how much mass is contained within a given volume. It determines whether an object will float or sink in a liquid.

4. What is the principle behind objects floating or sinking?

The principle behind objects floating or sinking is Archimedes' principle, which states that the buoyant force on an object is equal to the weight of the fluid that the object displaces. If the weight of the object is less than the weight of the fluid it displaces, it will float. If the weight is greater, it will sink.

5. Does the shape of an object affect its ability to float or sink?

Yes, the shape of an object can affect its ability to float or sink. A wider, flatter object will have a greater surface area and displace more liquid, making it more likely to float. A narrow, compact object will have less surface area and displace less liquid, making it more likely to sink.

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