insane_alien

i'm writing part of an essay about atmospheric dispersion and doing a thermodynamics assignment. and then i read this. it also struck me that the atmosphere is essentially a carnot cycle. (also if you have a carnot cycle without the transfer of heat then you do not have a carnot cycle.) so, there is an example of a carnot cycle without intelligence. it only needs the sun.

http://www.icantbelieveitsnotscienceforums.net.net

Apparently its because your DNS hasn't updated or something. i get the same thing and thats what blike said in the chatroom.

stratopause and under i think. they mostly stay below because they are created on the surface and winds rarely transport significant quantities of air above that. although if you do it by density then the closer to the ground the more.

yes it would take a lot of force to significantly change to orbit of the moon. and you calculated a force that big. thats the force holding the moon in place right now. doubling it would severely alter that orbit.

we know. or at least i know. don't know about the rest of them. they seemed a bit serious about it.

and some proper english wouldn't go amiss either. unless your ISP charges by the character.

yeah, i know. but you calculated the force the earth is supplying to keep the moon in orbit. the force the chain has to withstand will be a LOT less than that. i'll go see if i can find an example to explain it. okay, i can't find the place i was thinking about so i'll have a go myself. We'll use a 'traditional' space elevator instead of one to the moon to keep it simpler. okay. contrary to intuition, the greatest forces woldn't be at the ends but the middle. more precicely, geostationary orbit altitude. the force at the earth station could be zero in theory but would probably have some arbitrary force for tension and control purposes. this is because the cable is in orbit. a geostationary orbit. the cable below this altitude is dangling from the part at this altitude and the part above is moving faster than orbital velocity so trying to fly outwards. a counterweight like a small asteroid is likely to be used to reduce the length of the cable above. the end on the counter weight will be providing some centripetal force but not ALL of it like you were calculating for the moon. the force at the counter weight would be the force required to lift the entire cable minus the bits above geostationary and a bit more for orbital effects. it would not be the force of gravity between the asteroid and the earth. i hope you get it. another point of veiw is that if you did attach a chain to the moon that provided that force then the moon would start to accelerate towards earth. it's in equilibrium now and you're talking about doubling the force acting on the moon. thats a big force. the time it spends accelerating towards the earth would depend on the cable elasticity but it would definitely throw its orbit out of whack.

ehh, thats not the force the chain would need to apply. thats the force of gravity between the earth and moon. which exist now. to have a chain dangling beween the earth and moon it would only need to support its own weight.

irregardless, if you are holding the piano stationary, there is no work done. your muscles expend energy to keep applying the force but there is still no work done on the piano.

if you hold it stationary then there is absolutely NO work done no matter how you hold it. Work = Force times Distance. since its stationary, Distance = 0 m, therefore Work = 0 J

why would that hurt him? most tv shows take longer than that to get everybody looking perfect.

you could always use a lot of pillars to make an interference pattern. just make sure your standing at one of the places that experiences destructive interferance (destructive to the wave that is)

not you. the first guy. not sure what you're like yet so i can't say anything about you.

finally, we get some advanced warning so we can download some of the older pages to get out SFN fix while the servers down instead of having to go cold turkey.

nice to see common sense prevail. lets hope this sets a trend.

both. for everyone else, i made a mistake the first time round and edited it to say <wait, made a mistake> then i edited it again and put up the right answer.

your missing a water molecule and a hydrogen molecule from the second equation

you're not too clued up on energy are you?

the object does not need to be rotating to have a torque applied. an example is when your trying to turn a nut with a spanner but it doesn't move. your still applying a torque but nothing is rotating. T=F*r most basic definition you can get.

well, you see. if you looked at the sticks then both would be getting shorter. this is time and space rotating into each other. this part of the effect is called length contraction.

force acting perpendicularly to the axis of rotation at distance r. you really should use google for questions like these.

well, there is no stick. its the time between two events in relation to the observer. the outside observer would observe the pace slowing down. but the inside observer would witness the same happen to a clock outside. it would appear to slow down as well. this is where it gets confusing and in my current state of mind(hungover) i don't think that i'll be able to think about it without forcing my brain out through my ears.

if its from the point of view of an observer in the same frame as the event that gets slowed down then the event would appear to be happening at the same rate. she/he/it wouldn't notice any difference. an outside observer would. an example of this is ground level muons. by classical theory they shouldn't get down this far without decaying. if you include the relativistic effect of time dilation acting on the particles due to their high velocity compared to our frame then its perfectly reasonable for them to get down this far. time for them is running slower compared to us from our reference frame.

yeah, but we cant get a big stick that can be jammed between two points in time since we have no real control over our velocity and position in it. so we measure regular events. you can take the event as sticks. we count how many sticks are between two events. distance uses a stick, time uses the emmision of radiation. dimensions aren't defined by how they are measured.