And lo on Fri, 18 Jan 2008 03:00:21 -0000, Chambers  
<ben### [at] pacificwebguycom> did spake, saying:

> Phil Cook wrote:
>> And lo on Thu, 17 Jan 2008 04:35:39 -0000, Chambers  
>> <ben### [at] pacificwebguycom> did spake, saying:
>>> While volume != mass, as your rooms grow in volume, the mass needed to  
>>> enclose them also grows.
>>  No not really if you break it down to the simplest situation which is  
>> just the one room, simply expand the room and section it. Okay the  
>> external walls may be thicker then the internal ones, but the principal  
>> stilll holds.
>
> ?
>
> This is like saying, "You're right, but you're still wrong." :)

Yup :-)

> Tim said, "Space is at a premium in just about any vehicle.  You use as  
> little as possible. "
>
> My reasoning is that addition volume means additional materials to  
> enclose it, and additional fuel needed to propel it.  I never stated  
> that the relationship between volume and mass was a linear one.  In  
> fact...
>
>>> It's not a linear relationship, but it is there.
>
> In other words, volume and mass are related (the relationship is there),  
> but not in a linear way (it's not a linear relationship).

Which I first pointed out and subsequently kept agreeing with.

>>>> Create a 7 unit cubic room with walls massing 1kg per square unit  
>>>> (all the same thickness). You're pumping it full of a gas that masses  
>>>> 0.1kg per cubic unit. So the mass of the initial room is 328.3kg. Now  
>>>> increase the height of the room by 1 unit and you get 361.2kg a ~10%  
>>>> increase in mass for a ~14% gain in volume. Make it all 8*8*8 and you  
>>>> get a ~49% volume increase for a ~32% mass increase.
>>>
>>> But what is that 32% mass increase is not feasible?  What if an  
>>> additional 10% isn't feasible?  This is a government funded project,  
>>> remember, and their budget is spread over many things - not just the  
>>> rec room for the astronauts.
>>  No you're conflating feasible with cost, the budget that has been set  
>> is
>
> No, I'm saying "What if".  The point is, you blithely point out that  
> additional materials are needed, and then say that the additional cost  
> doesn't matter, while I say that the additional cost may make a  
> difference.

But the start of this conversation was about the Jupiter mission in  
2001:ASO. A society with a space base and moon bases. So the money is  
there I didn't see them ducking through doors on the moon base so Alain's  
perimeter argument seems only to apply to ships and not stationery objects.

>> Except what I'm saying is there was no need for it to be "a bit  
>> cramped" at all. Having a 300ft square bedroom is overkill, having a  
>> 7.5 cube instead of a 7 cube isn't.
>
> But this room isn't the only one in the spaceship; that extra .5 cube  
> (?) needs to come from somewhere.
>
> Assuming that the outer hull of the ship is fixed, and cannot be  
> enlarged, then it means you have to take .5 cube from another room.
>
> Assuming that the outer hull of the ship CAN be enlarged, then we don't  
> need to change the size of the rooms, but we do need additional  
> materials.
>
> Anyway, the point is that making things bigger has a cost.  It's naive  
> to say simply, "They should have made that bigger," without at least  
> examining the costs.

And again you're correct in the same way I say a 300 ft room is overkill.  



-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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