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Prolifical ENG
11-06-2006, 11:29 AM
I guess we could use a thread about physics, since it can come up in many topics in KTL and briefly comes up once in a while.

Ill leave this thread like this for now and see where it leads.

HANZO
11-06-2006, 11:33 AM
if everyone on earth weighed 100kg and jumped at the same time while standing at the north pole there is a high chance that the earth will move from its axis. i actually calculated this and mathematically with the relation with newtons laws, so in theory it should work.

Prolifical ENG
11-06-2006, 11:37 AM
if everyone on earth weighed 100kg and jumped at the same time while standing at the north pole there is a high chance that the earth will move from its axis. i actually calculated this and mathematically with the relation with newtons laws, so in theory it should work.

do all the people at the north pole need to stand exactly at that geographical point? or is there a certain area that you alotted? how high does everyone have to jump on average?

write down your calculation work if you still have it.

HANZO
11-06-2006, 11:46 AM
if everyone stands acorss the globe in different places then the momentum would cancel each other out. to exert enough force so that the entire momentum would be greater than the earths everyone needs to weight 100kg and the force must be exerted on a specified area.

i didnt include height in the calculation but it obviously had to be concidered, but my physics isnt strong enough to add height into the equation.
the basic principle of this is that everyone jumping at the same time will make people weight heavier than the earth meaning that it will push the earth of its axis.
if i could find the calculation i post it up or try it again. my physics has gone rusty, now that i study aerospace engineering the physics i do is all about motion and electronics which is boring. astrophysics is were all the interesting stuff is at.

Sexy Jasper
11-06-2006, 12:56 PM
I find it pretty fascinating how they can emulate physics in videogames. That must be some really complex stuff.

the silencer
11-06-2006, 11:18 PM
i just finished reading Stephen Hawkings a Brief History of Time last night....definietly mad informative and interesting but he got waaaay to technical and nerdy sometimes and seemed to forget that theres a possibility his reader is somebody who's not well-versed in physics...

started reading Brian Greene's Fabric of the Cosmos last night and im fuckin lovin it....this dude can write really well....so far hes basically sayin the same stuff that was put forth in the Hawking book but Greene makes it easier to understand and actually makes u interested in it with the examples he uses and shit....GREAT book.....recommended to anybody wantin to get a grasp of how shit works in the universe..

Prolifical ENG
11-07-2006, 06:19 PM
I find it pretty fascinating how they can emulate physics in videogames. That must be some really complex stuff.

I dunno.....after you know so much math, its just a bunch of variables and constants. just twiddle with the constants until it looks realistic...and also need to speed it up just a little...you walk faster in a first person video game than in real life.

well thats what I thought the physical part of those games were.....most of those games that have first person shooters probably already have most of the programs already made and they just adjust the variables.

SG
10-14-2008, 07:07 PM
When you select this link, maximize the window of planet earth.
Click here (http://science.nasa.gov/Realtime/jtrack/3d/JTrack3D.html)
Go to options: update rate to ¼ second
Go to options: Timing x1000
…….the planet should start moving
Select satellite, under “TYPE” select physics. There are 10 satellites

TSA
10-14-2008, 07:27 PM
to Han, your jumping notion, im going to go calculate how much a planet of 100 pound ppl will wiegh cause i dont think it's more then da erff

Prolifical ENG
10-14-2008, 07:38 PM
who knows, Han wrote that 2 years ago....he might have stronger math and physics than me now....he might be able to incorporate more terms in and if they are significant.

but its the force of all those people jumping at once compared to the mass of the earth, not mass of people > mass of the earth.

earth mass is 6 x 10^24 kg....100kg people * 6 x 10^9 (population) = 6 x 10^11 then do the force of them all jumping, acceleration of 9.98 m/s/s with a height and you find the force and so on.

Thrilla24x7
10-14-2008, 07:53 PM
Ha, that problem is pretty advanced, there are hundreds of constants that contribute to the experiment.

Even if the people hit the earth with force "F", the gravitational force between the earth and other planets is much large than anything humans can produce, therefore reducing the Net force.

Prolifical ENG
10-14-2008, 08:44 PM
Of course, there are lots of constants (terms) but they are all on different magnitudes. small enough in magnitude and you can neglect them. Of course in dynamics the challenge is picking which terms to keep and which to throw out. I never thought the other planets would compare to the Earth-Sun...Venus-Earth might have some but thats because of its unique orbit coupling.....I could be wrong, I deal mostly with meteorological dynamics.

I guess we are taking Hans exercise a little too far...was probably for his first year at uni with newtons laws

TSA
10-14-2008, 09:10 PM
anyways im looking at it and dont know how many kilograms are in a pound but it doesn't look right

plus from my limited understanding wouldn't we have fucked up the gravitation of earth if we weighed more then it or even as close to as much as it?


earth in kilograms
6,000,000,000,000,000,000,000,000

rough estimate of how much we'd all weigh if we were all 100 pounds
600,000,000,000

but a 600,000,000,000 pound object hitting the earth is crazy real in da vil

firewood_for_hell
10-14-2008, 09:20 PM
the sun causes graviity not planetary mass
throw your school text books away and forget them

Prolifical ENG
10-14-2008, 09:34 PM
^^^never read a school physics textbook


gravity and mass, they are all related.... gMm/r^2

TSA
10-14-2008, 10:38 PM
wait, that 600,000,000,000 pound object(the ppl jumping) don't have the distance and speed to actually cause significant change, just da mass, but the guy goes to school for this shit so i'll shut up

Thrilla24x7
10-15-2008, 11:12 AM
gravity and mass, they are all related.... gMm/r^2

^That's exactly right, The gravitation force bewtween to masses(planets),thats the factor that needs to be looked at.

IrOnMaN
10-15-2008, 11:47 AM
I like Physics but Jesus Christ! I've taken two semesters of General Physics (including those bullshit labs) and they were pretty straight foward and weak. I understand why I need physics because it helps geologists understand things earth processes ALOT more better. Physics can be boring at times, depending on the situation and who's teaching it.

However, I LOVE Astronomy! In fact, I've always wanted to major in astronomy but the university I attend doesn't offer astronomy as a major, until now. Couldn't I have just majored in physics and become an astronomer that way?

HANZO
10-15-2008, 12:17 PM
who knows, Han wrote that 2 years ago....he might have stronger math and physics than me now....he might be able to incorporate more terms in and if they are significant.

but its the force of all those people jumping at once compared to the mass of the earth, not mass of people > mass of the earth.

earth mass is 6 x 10^24 kg....100kg people * 6 x 10^9 (population) = 6 x 10^11 then do the force of them all jumping, acceleration of 9.98 m/s/s with a height and you find the force and so on.

basically thats how its calculated

the whole notion is that enough force would be created to slightly edge the earth off its axis. impact force as they call it. you would need everyone to stand on top of each other on the north pole though. cause ppl jumping at different angles (due to the earths curvature) will cancel out the forces, so it wont work.

but cause everyone standing on top of each other the surface area is incredibly small, so when the ppl jump, instead of moving the earth they will just drill down it. like a knife.