Buoyancy and gravity

[TheOldDog]

As I showed in post #23, changing to mass actually made it more complicated because when formulated as a mass equivalence Archimedes principle can be violated in a non-uniform gravitational field, whereas formulated in terms of weights it always works.

For my example the water and the boat experience the same gravity.

 

[haruspex]

50 yrs ago that's what we did in school. When we used mass it was in grams, when we used weight it was in pounds.

Bizarre. But you understand now that one should use
- pounds mass for mass and pounds force for weight ,
- or kg for mass and Newtons for weight,
- or g for mass and dynes for weight…
right?

 

[sophiecentaur]

the artificial gravity did not vary over the positions covered in the story.

I think this could be very relevant to this thread and could be difficult to achieve in practice (assuming the 'impossible' were actually possible). A huge ship would be involved - much bigger than needed just to make it 'feel right' for the occupants. I think a story would need to be involve consideration of the effects of non linear gravity.
There's a basic difference in the behaviour of solids and liquids in non uniform gravity. Forces (pressure) are transmitted through a liquid in a hydrostatic way but the force through a solid object would be transmitted by electric forces would be transmitted via intermolecular electric cores.

Consider the above diagrams applied to solid and liquids.
The resulting forces / pressures on liquid shapes and solid shapes differ and it's only simple under uniform gravity. That's basic stuff. I'd say that you have to do without the assumption of uniform gravity for any vaguely practical situation. It could cause some interesting divergencies from our regular experiences which could enhance the interest in a story line.