# Yo Rayne, Math Shit

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• 03-27-2012, 08:54 PM
Kirby
Yo Rayne, Math Shit
I know I already posted this on cosmo, but maybe with it's own separate thread it would gain validity.

I am trying to calculate much explosive energy an Asgaurd lazer has. Without boring you with the scifi specifics to much, basically I first tried to find it out using the power output of the space ships power source, which is 1.21 gigawatts. Using a calculator found here http://www.translatorscafe.com/cafe/...on-%5Bkton%5D/, I did gigawatts to kilotons, getting a mere 1.041108987 kilotons, which is pretty pathetic for the strongest weapon in stargate, so I assume the output is wrong.

So I tried something else. Another fact is the power source can hold the weight of the ocean over the city about the size of Manhattan. For this I first took the weight of water per meter 1000 kilograms, multiplied it by average depth of the ocean: 3,790 meters, then by area of Manhattan 87500 meters. Finally I multiplied that by the gravitational constant of 9.8, which should get the force in joules. So you get 3249925000000 joules, which using the same converter is again a low 0.776750717 Kilotons.

Something is off here, and it is really bothering me, help me out.
• 03-27-2012, 09:00 PM
Celery
How much ocean, all ocean or just as much ocean to cover the city?
• 03-27-2012, 09:03 PM
Kirby
The depth of the ocean which for simplicity purposes I am saying 3,790 meters, over an area the size of manhattan: 87500 meters.

This is all per second too, so don't worry about time.
• 03-27-2012, 09:04 PM
Kirby
My pain problem with this is I doubt .7 kilotons of explosives could hold the weight of the ocean.
• 03-27-2012, 09:21 PM
God
the power it takes to LIFT the water above the city would be a lot more than it takes to hold it there
• 03-27-2012, 09:33 PM
Rayne
I don't understand how you can convert a unit of power into weight.
• 03-27-2012, 09:33 PM
Kirby
I guess I will just have accept that Stargate lazers are incredibly weak, yet still the strongest in the universe. Fat man was 22 kilotons for christs sake.
• 03-27-2012, 09:35 PM
Rayne
I've been awake for 25 hours. Maybe I'll try and figure it out later.
• 03-27-2012, 09:35 PM
Kirby
Quote:

Originally Posted by Rayne
I don't understand how you can convert a unit of power into weight.

Force from can be transphered to energy, which then can be transphered to explosive power. 9.8 is the constant I believe you need to make this conversion from some quick internet research, so I might be wrong.
• 03-27-2012, 09:35 PM
Rayne
By 'it' I mean how much power is required to lift and hold up the water.
• 03-27-2012, 09:38 PM
Rayne
Quote:

Originally Posted by Kirby
Force from can be transphered to energy, which then can be transphered to explosive power. 9.8 is the constant I believe you need to make this conversion from some quick internet research, so I might be wrong.

You're definitely wrong. 9.8 is the acceleration due to gravity of the earth. It can probably convert a mass to the amount of force necessary to move that mass against the effect of gravity but you'd need a lot more data to figure out the energy/power.
• 03-27-2012, 09:39 PM
Rayne
Also 'convert' is entirely the wrong word
• 03-27-2012, 09:53 PM
Rayne
Average ocean depth = 4.3 km.
Area of manhattan = 87 sq.km
Volume of the water above the city = 374 cubic km. = 374 x 10^9 cubic meters.
Density of water = 1 gram per cubic centimeter = 0.000001 grams per cubic meter.
Weight of the ocean water = 374000 g
Force required to lift up the mass (let's assume acceleration is equal to 10 m/s^2 since it needs to be greater than the acceleration due to gravity, which is 9.8, to counteract it) = 3740000 N
Work that needs to be done to lift it to a height of, say, 1 km = 3740000000 joules
• 03-27-2012, 10:02 PM
Rayne
Hold on that math is completely off.
• 03-27-2012, 10:09 PM
Rayne
I'm too fucking sleepy. I'll think about it later.
• 03-28-2012, 04:18 AM
Kirby
The cities hieght is 800 meters.
• 03-28-2012, 05:27 PM
Rayne
Quote:

Density of water = 1 gram per cubic centimeter = 0.000001 grams per cubic meter.
lol how did i get this. so stupid.
• 03-28-2012, 05:33 PM
Kirby
that is pretty funny actually

the problem is only you noticed it :-X
• 03-28-2012, 05:43 PM
Rayne
anyway, weight of the water = 374 x 10^12 kg
downward force due to gravity = 374 x 10^13 N
you'll need a greater force to counteract it. lets assume it to be around 400 x 10^13 N
the net force on the water = 26 x 10^13 N
the acceleration produced due to that force = 0.8 m/s^2
to scale a distance of 800 m, it would take (2x800)/0.8 = 2000 seconds
the work done to move the water to 800 m = 20800 x 10^13 J = 2.08 x 10^17 J
so the required power is approximately 1 x 10^14 watts = 10,000 gigawatts

so essentially you need around 10,000 gigawatts of power to lift up an ocean to a height of 800 m above manhattan in approximately half an hour. to hold it up there you'll need a negligibly smaller amount of energy every second.
• 03-28-2012, 05:45 PM
Rayne
oh yeah the original question: your space ship thing has a laser of power output 10,000 gigawatts.
• 03-28-2012, 05:47 PM
Rayne
but i dont know how fast it can get the water up there oh wait i dont even fucking care why am i doing this
• 03-28-2012, 05:52 PM
Kirby
8604 Kilotons that is more like it

Thats like 4 modern nukes, I can live with that. Still 6 times weaker than the largest russian bomb(50000 kilotons, but whatever.

So about 25000 kilotons to take down a wraith hive ship.
• 03-28-2012, 05:53 PM
Rayne
where the hell are you getting kilotons from
• 03-28-2012, 05:57 PM
Kirby
Pictures to amuse myself in showing you what I just showed:

this:
http://watchcsionlinefree.yolasite.c...=1280737074454

to this: