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beatrix kiddo
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chroot, doesn't the Earth have kinectic and potential energy as it revolves around the sun? would this mean that there is work being done? or, because there is conservation, no work gets done?
Quite simply, no.urtalkinstupid said:That's the point I'm trying to argue. Energy is created in order to keep that force constant. In order to make a force applicable, there is a needed input of energy.
Both magnetism and gravity are conservative forces, which means they conserve energy. If they were not conservative, there would be serious consequences in the behavior of such systems in translations in time, which would pretty much rewrite physics from the ground up -- and it'd be entirely wrong. The conservation of energy and the concommitant invariance of physical laws to translations in time are perhaps the most fundamental properties of physics in this universe.As Chrono's said, there is the same problem with permanent magnets, except much greater, because they hang on a refrigerator door like mountain climbers hang on the side of a cliff.
Which equation? [itex]W = \vec F \cdot \vec d[/itex]? The one that you don't even understand?This all ties into the Work equation.
Temperature and heat are not the same thing at all.urtalkinstupid said:The change in heat would be more reasonable. You take the final temperature and subtract from the initial, right? This gives the total amount of heat put into the system.
urtalkinstupid said:Wouldn't that be:
[tex]E=\Delta q +W[/tex]
The change in heat would be more reasonable. You take the final temperature and subtract from the initial, right? This gives the total amount of heat put into the system.
It is not how we define work.JoeWade said:since that's how we DEFINE "work" maybe you'd better use a different term.
You've yet to substantiate this claim.urtalkinstupid said:There is a required source of energy to exert work on an object.
Magnetism is a conservative force. A human's muscles pushing something do not constitute a conservative system.If a magnet is said to do no work, how is that possible? We know it requires a force to act against gravity to stay on the refrigerator, but no work is done, because it doesn't move anything. In examples ithat nvolved pushing stuff, the energy is transferred into heat, if nothing is moved. What is the case with the magnet?
chroot said:It is not how we define work.
- Warren
Now, since the orbit is actually elliptical, and potential gravity energy drops as the moon approaches earth, this energy needs to go somewhere. It ends up as kinetic energy, making the moon move faster as it approaches earth, and, therefore, moving slower as it recedes.
Understand?
Now, notice that energy is NOT a vector. This means that a change in direction WILL NOT CHANGE ENERGY AT ALL. You can rotate the speed all you want, you have the same kinetic energy.
beatrix kiddo said:it's ok, tran.. my post was old...
yeah.. that's why i didn't do a follow up post...
u really, REALLY don't have to tell me energy isn't a vector..
Because electromagnetic forces are calculated in the same way gravity is, the same "different energy" argument applies. However, as was already stated, the force/work/energy/I'm really not sure, not my area from gravity is spread through the molecular bonds in the atoms that the magnet is 'latching' onto. (right?)urtalkinstupid said:Yes, temperature is a measure of heat. Sorry for that. There is a required source of energy to exert work on an object. Energy is related to force. We've established that through a poorly derived equation. I'm sure a little more work we can get a nice relationship.
If a magnet is said to do no work, how is that possible? We know it requires a force to act against gravity to stay on the refrigerator, but no work is done, because it doesn't move anything. In examples ithat nvolved pushing stuff, the energy is transferred into heat, if nothing is moved. What is the case with the magnet?
urtalkinstupid said:Force is related to Energy, Force is related with work, so Energy and Work are related.
I was not saying energy was a vector that can be applied in a direction. The energy is spread out (scalar), while force is applicable in a direction vector). Are you trying to tell me that work is not scalar, so I can't relate Energy to it, because it contains a vector? I'm not getting it.
urtalkinstupid said:You can convert scalar to vector and vice versa.
This is not difficult to understand. I'm no longer amused and I no longer believe there is any chance you kiddies are making an honest effort here.chroot said:This is not difficult to understand.
- Warren
beatrix kiddo said:chronos u can convert from scalar to vector.. and russ we aren't trying to amuse u..
Math Is Hard said:why would you do that? I am not sure I follow...? For instance, if you take away the directional component of a force and only have a magnitude of acceleration (times mass) remaining, doesn't that leave you with a push or pull in no direction?
But maybe I don't understand what you mean by "convert".
No, you're probably just trying to amuse yourselves. Regardelss, the only reason you two are still members here is you are amusing to us (except a small possibility others are learning from your mistakes). Our patience, however, has limits.beatrix kiddo said:...and russ we aren't trying to amuse u..
urtalkinstupid said:You can convert scalar to vector and vice versa.
No, you're probably just trying to amuse yourselves. Regardelss, the only reason you two are still members here is you are amusing to us (except a small possibility others are learning from your mistakes). Our patience, however, has limits.
Its simply not possible for you two to not be smart enough to understand it. That means you guys are choosing to not understand it. Why, we're not sure, but regardless, you are not making an effort to help yourselves and you are not making a positive contribtion to this board.
*Elementary school analogy: A car stationary at idle does no useful work. All of the energy input by the engine is wasted as heat, either dissipated by the radiator/engine block or blown out the tailpipe.
You can get a scalar from a vector (by taking the modulus for example), but you can't get a vector from a scalr without introducing another vector.
so Energy and Work are related.
jcsd said:You can get a scalar from a vector (by taking the modulus for example), but you can't get a vector from a scalr without introducing another vector.
basically u see stupid and me as a couple of clowns here for ur enjoyment... and ur patience is limited... what's going to happen when it runs out? are u going to close this thread down, too?