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." :)

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).

>>> 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.

> 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.

-- 
...Ben Chambers
www.pacificwebguy.com

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