swansont
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Viewing Topic: At what point is violent civil unrest against a government justified?
Everything posted by swansont
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what if the angles on a triangle DIDN'T add up to 180*?
It would mean you aren’t in a cartesian geometry, i.e. it’s not flat. The sum of the angles will depends on the geometry.
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Curious device
A large structure does not have to bend very much to account for this energy. As you say, it is a tiny metal sheet. If you lift a 1 g object 1 meter, a 1 kg structure only has to shift 1 mm Physics is quite successful, but relies on rigor and not hand-waving.
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The brain is nothing more than an electronic device. So, every electronic device with a lot of wires, swiched on should be conscious too
Logically incorrect, even if the premise is true. Equivalent to “All dogs are mammals. I am a mammal, therefore I am a dog.”
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Curious device
No. It’s just that there’s no real difference. In one case it’s a person doing the work, in another it’s a structure doing it. The magnetic field is doing the lifting, just as with a chain, but it’s not doing the work. Do you know what “work” is in physics? It has a specific definition, as I explained in an earlier post. It’s not some general idea of effort or force. Work has units of energy; it’s energy transferred because of a force acting through a displacement. Magnetic forces do not do this; they are perpendicular to displacement. If a magnet is held by a structure, that structure will flex under a load; that is the source of the energy (energy stored in the structure’s configuration, and/or a reduction in its potential energy because the structure shifts downward) As I said, there’s no such thing as a perfectly rigid structure.
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hijack from Can you be a scientist and still believe in religion?
! Moderator Note Preaching is not permitted here. You mention this in numerous posts, and it’s irrelevant to the discussion. ! Moderator Note Posting to advertise your other threads is also against the rules.
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Curious device
I’m saying if you lift something with a magnet, you are supplying the energy, not the magnet. It’s not different, conceptually, from attaching a chain to something and lifting it. The chain is involved, but it’s not supplying the effort to lift the object. The chain doesn’t have a store of energy that does the lifting. It doesn’t matter how convoluted or clever a scenario you come up with. The energy to do the lifting (which is what work is, in physics - the energy supplied by exerting a force through a displacement) comes from somewhere else.
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Curious device
Dodge? You’ve been told that the work is done by external, mechanical means. All dipole magnets act like a current loop (permanent magnets, too) and the force on a current is IL X B. That’s a cross product - the force is perpendicular to the current and external field. Work is a dot product of the force and displacement. The work is in the common direction of the force and displacement. Since the force is always perpendicular, this dot product is zero. There is no work done. No energy comes at the expense of the magnetic field. It doesn’t matter if the magnetic field is from a permanent magnet. It doesn’t change if you try coming up with some clever configuration. The work is always mechanical or electrical. The magnet isn’t depleted, which must happen if the magnet is doing the work, and this would happen pretty quickly if that’s what was happening.
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Curious device
Do you understand that “fixed” is only an approximation? There is no such thing as a perfectly rigid structure. Which means that the mechanical structure flexes. There are mechanical forces, and they act through a displacement, i.e. they do work. Because that’s involved in magnetic attraction. You have to understand a bit of physics to appreciate the answer. If you don’t, then the answers might look like obfuscation or irrelevance. But you have an obligation here, because demanding an answer that involves a couple of semesters worth of physics, without having that knowledge, isn’t reasonable.
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Curious device
Is the magnet hovering in space? I don’t think that’s happening. (Further, what happens in the metal? You get an eddy current. The force doing work there is electric, not magnetic.) The work - the energy input - is not the magnet. It’s something else. Magnets don’t get energy depleted by being used. They are not the source of the change in energy of the system.
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The 'Rapist's Bible'
Just like with any other product. Trump markup. That’s the point of this grift. Or there is no copyright attached, which would be the case for the Bible. I’m shocked, shocked, that deceit is going on here. A scam? Involving Trump? The deuce, you say! </s>
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Curious device
I’m saying you aren’t looking very closely at what happens. A magnet does not magically move into place to lift something, and when it is moved, work must be done in doing so, and during the lifting process. By the system or person moving the magnet. The magnet is an agent of transferring the force you are exerting, but the work done is by you, not the magnet.
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Curious device
The work done is provided by whatever or whoever is holding the magnet. The magnet does not move into position where it can lift by itself.
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Curious device
Magnets are another example of redirecting; magnetic forces are perpendicular to motion, so they do no work.
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ECA stacking in weightloss experiment
! Moderator Note Countries not banning it is not evidence of safety, the information about adverse reactions including death are easily found with a search, and it is not for you to set the limits of what can be consumed.
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Curious device
So the input is where the work is done. And the work will be done by you in moving the magnet - it takes more effort to move a magnet in the presence of another than it does in free space. That’s you doing work, not the magnet.
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Curious device
Magnetic forces don’t do work. If you built this, you would see that it doesn’t run on its own. If you stop cranking, it will cease motion.
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Curious device
The work in this system would be provided by whatever is turning the input rotor. Nothing inside the device is supplying energy; there are only losses to be found there.
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Introducing Edge theory. It's like String theory, except...
! Moderator Note This is very much the forum for getting testable predictions. It’s a requirement. Teasing that you’ll get to “the meat” is something we’ve seen before, and it never pans out. You’ve not given any indication that this will be different, and if you don’t deliver (and soon) the thread will be locked. A journal? With peer review? Are you going to make preprints available? I don’t understand. What are “these problems”? How are they growing larger? How do you conclude that standard physics won’t solve the problems? Cosmology isn’t a huge slice of physics, though it’s more visible (as it were) than other areas.
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zip file with password on mobile devices?
The second side was not brought up in the OP, which was simply asking if there are ways to password-protect files.
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zip file with password on mobile devices?
I’ve had documents sent to me that were password protected. Microsoft docs and pdf files
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English nick suggestion?
I hope H didn’t stand for “Hugh”
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English nick suggestion?
To me a shortened version of a first name is not a nickname. i.e. I don’t consider ”Tom” to be my nickname. Nicknames I’ve had are Swanny (grade school) Stouffer (college), Puft (navy OIS), none of which are gender-specific. SNL had a series of sketches about gender-neutral nicknames. The lead character was Pat, and nobody knew their gender. Also mentioned are Terry and Chris, and homophonic names like Frances/Francis, Jean/Gene
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Intuitively, why doesn't always picking unpopular integers lower Probability of winning lotteries?
It’s random - any pick has the same odds of winning. Picking unpopular number increases the odds that, if you win, you will be sole winner, or at least have to share with fewer people, as your quote says. So the expected payout increases.
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What if humans were to have not otherwise evolved as male and female in separate bodies?
Animals (specified in the OP) ≠ organisms Plants can be male & female Where does the other genetic material come from if the individual self-fertilizes? If there are two, then you’re doing what sexual reproduction does, so it it’s an advantage, then it’s an advantage. And AFAIK most hermaphroditic animals are invertebrates so there might be some limits on that mode of reproduction.
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Sunshine on Titan
It describes a magnet in terms of the torque the magnet would feel in an external field A magnetic dipole (e.g. a bar magnet) with moment u in a magnetic field (B) feels a torque of u X B (u is a vector) The magnetic moment of a wire loop with area A and current I is u = IA (with a direction given by the right-hand rule)