Re: "Rockets not carrying fuel" and the space tower.

Apr 06, 2005 4 Replies

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Brian Whatcott 21 years ago

>>>
>>>
>>> The following analysis is acurate to 3 significant figures.
>>>////
>>> p = 1000 kg/m^3 (density of water @ STP -101kPa &
>>> 25C)
>>>///
>>> g = 10kg*m/s^2 (Gravitational constant for planet Earth
>>> - the planet we live on for those that don't know)
>>> Dwayne
>>
>>
>> "The following analysis is accurate to 3 significant figures."
>> "g = 10 ms^-2 Gravitational constant for planet Earth"
>>
>> Very amusing - I especially liked the gravitational *constant* part -
>> apparently independent of altitude.
>
>The radius of the Earth is 6378km, so 100km is negligible. I used 3 sig figs
>in the calculation. Please learn the scientific approach before critisizing >my work.
>
>Dwayne
>

I know I shall regret this: but, for what it's worth:

1) stp means standard temp and pressure, which implies temp = 0 deg, not 25degC
2) g is usually 9.81 m/s^2 but it varies a little from place to place.

Brian W

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N:dlzc D:aol T:com (dlzc) 21 years ago

Dear Brian Whatcott:

I concur. However he did *define* his "standard" reference to one of the 3 or 4 values I have seen defined as "standard". ;>)

David A. Smith

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Lady Chatterly 21 years ago

So many tards, so little time.

-- Lady Chatterly

"How can a bot be a tranny, dumbass?" -- Peter Hood

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Dwayne 21 years ago

Both, for some bizzare reason are correct. My thermo book says 25C, a brief web search suggests 0C.

Dwayne

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Brian Whatcott 21 years ago

///

[trimmed the distribution to eng groups]

Density of water is about 1 gram per cc or

1 kg per 1000 cc = 1 liter = 10 cm X 10 cm X 10 cm

To put it in plain English: a box of water 10 centimeters on a side weighs 1 kg or in plainer English a box of sides 4 inch long, full of water weighs 2.2 lbs

Punch line coming up: you can fit how many boxes, 10 cm on a side, into a box of 1meter X 1 meter X 1 meter?

On one face, 100 boxes will fit, and you can fit another 9 layers like it to quite fill up the bigger box. That's 100 X 10 = 1000 small boxes in a cubic meter. Each small box weighs 1 kg The big box weighs 1000 x 1 kg = 1000 kg or 1 million grams.

Brian W Altus, OK

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