Archimedes Schmarchimedes

[Kirstie]

Originally Posted by Finless

The "it" in your example being Kirstie?

And the rest of you can stop perving .......... I'm sure Kirstie is fully clad in the bath!!!

I always wear my swimmies to bath in.

What's a PSP? I haven't seen that, either in the bath or anywhere else.

[chrisch]

Originally Posted by Kirstie

I always wear my swimmies to bath in.

Chris

[wilbo]

does this help at all?

Buoyancy - Wikipedia, the free encyclopedia

[Kirstie]

That's me in my dive kit in Tenerife!

[Kirstie]

Originally Posted by wilbo

does this help at all?

Buoyancy - Wikipedia, the free encyclopedia

It does help, even though there's lots of maths in it.

Thank you.

[Diogenes]

Kirstie

I'm sorry I don't have any more examples to point you to so you can work through them. I post merely to offer my condolences for you're asking the question and getting so much accurate...yet somehow unhelpful...information.

[Kirstie]

Originally Posted by Diogenes

Kirstie

I'm sorry I don't have any more examples to point you to so you can work through them. I post merely to offer my condolences for you're asking the question and getting so much accurate...yet somehow unhelpful...information.

LOL, to be fair a lot of it is helpful - I've printed off a few attachments which I'll read through in the hope that the penny drops

My problem is that I convince myself I'm not going to understand before I've even tried.

[Conor]

I find it easier to do it in steps

Work out the volume in litres of the thing to move, that'll be the volume of water thats displaced. U

Using 1kg/l (or 1.03 kgl) the weight of the water displaced is approximately the same as the volume of the water displaced.

To be neutral the object displacing the water should eb the same weight.

To go up it should be lighter, to go down it should be heavier.

Thats the basic bit, so onwards to lifting something.

If you have something at the bottom you want to lift that ways 2kg and occupies 1kg of volume, according to the above it is 1kg negative.

Therefore to make it neutral you need to displace a further 1kg of water so you would need a container of about 1 liter (in fresh water etc) filled with air.

The amount of gas needed to fill the object would be determined by depth, so at the surface you need 1 surface equivalent litres of air, at ten meters you need 2 surface equivalent litres of air, and so on.

The reason for 'surface equivalence' is that at the respective depths they are always 1 litre.

So for an example, an object weighing 1000kg with a volume of 700L is sunk in fresh water at 30m.

What size lifting bag would be required to make it neutral?
What volume of gas would be required to fill the bag at that depth?
If you have a 12L cylinder with you for lifting the object, what pressure would it need to have to contain enough gas to do the lift?

Sorry if all that is useless but it was interesting for me

[Diogenes]

You could also try here. It may be another way of trying to explain something that doesn't "stick" very well in the way you think.

Quite a few graphics for explanations and I like the term "Bobbies".

[Finless]

Originally Posted by Kirstie

LOL, to be fair a lot of it is helpful - I've printed off a few attachments which I'll read through in the hope that the penny drops

My problem is that I convince myself I'm not going to understand before I've even tried.

Just think .......... when it drops you'll know if it will be buoyant and, if not, how much gas to put in a lift bag to recover it! Incentive to learn if I've ever heard of it?