Is there a NON-HISTORICAL and functional reason that physics models currents as "conventional" positive flow?
109870
Nope. Ben just got it wrong.\n\nWhen he came up with "positive" and "negative" he wasn't even thinking in terms of current they way we do today. Frankline did have an "fluid theory" of electricity, but it was much different in scope with anything we would think of. It was not until 1897 that the electron was discovered.\n\nSo, Ben, can be forgiven. When he was working he wrote in a letter that "I feel a Want of Terms here and doubt much whether I shall be able to make this intelligible," and he supposed to have come up with a variety of terms in use today:     \n\n    * battery\n    * charge\n    * condensor\n    * conductor\n    * plus\n    * minus\n    * positively\n    * negatively\n    * armature\n\nUsing a positve flow is useful in that it keeps a lot of the quantities positive. (Though I confess, in Physics grad school we always used the electrons moving bit.)\n\nAlso moving protons are good if one wants to use special relativity to show that electricy and magnetism are the same.
1167649
Not quite! The direction the water goes down the plug-hole depends on whther you are in the northern or southern hemisphere. It has nothing to do with magnetic fields, but everything to do with the coreolis effect, which is caused by the direction in which the Earth is spinning.
692204
Just a minor nitpick on what others have said.  Electricity can also be the motion of holes, which can be thought of as the absense of an electron.  But generally it is the motion of electrons.
1134100
The nomenclature of positive and negative charges was decided before electrons were discovered.  The technology of the day couldn't distinguish between moving positive charges and moving negative charges, so they basically guessed that positive charges flow.  Positively charged objects were thought to have a surplus of charge carriers, and negatively charged objects were thought to have a deficit.\n\nit wasn't until vacuum tubes showed up that it was conclusively shown that the things that carry charge current carry a negative charge.  So, the original guess was shown to be wrong.  Rather than confusing everything by changing notation suddenly, we just persisted with the notation, counter-intuitive though it may be.
189365
u know water flows from higher altitudes to lower.ie, for the flow of fluids a hight difference is needed ,,interms of energy a difference in potential energy is needed.like that for the flow of current a difference in electric energy is needed .this energy difference is called potential difference.\n\n              if we connect an emf source to a resister,the energy difference form btn the terminals of resister
749223
The flow of current is caused by an electric field being applied to a material if there are electrons which are not tightly bound to the atoms in the material. \n\nIn a metal, an electric field will apply enough force to the electrons to allow them to move from one atom to the next, as long as there is a free electron to replace it. The free electrons may come from a battery, or a loop of metal wire spinning in a magnetic field, for example. The bond of the electrons in the outer atomic shells to the nucleus is not so strong.\n\nOn the other hand, for an insulator, even very high electric fields will not encourage the electrons in the outer shells of the atoms to leave the atom. They are tightly bound to the nucleus.
1130935
Yes, it IS possible that positive charges can flow in a conductor. Consider a solution of NaCl in water - this solution conducts electricity in the form of Cl- AND Na+ ions moving in opposite directions. In plasma, current is carried by both the free electrons and protons flying around. Electrical current is far more general than just the elementary-school simplification of electrons moving through a wire.
1086143
It's a law of electrical flow along a circuit.
810698
1. VERY PURE water is a poor conductor of electricity. However, very small \namounts of impurities, especially salts, greatly increase the electrical\nconductivity of water.\n2. The main carriers of electrical current are dissolved ions. If a \nbattery is connected to a container of water so that\nthe (+) and (-) poles of the battery are immersed in the water, the\npositive ions will migrate toward the (-) pole and the negative ions will\nmigrate toward the (+) pole (electrical opposites attract). This closes the\n"switch" and electric current flows through the solution.\n3. Different ions can help carry the electric current, some more / some \nless, depending upon their electrical charge and their size. More highly charged, \nsmaller ions are more efficient carriers of the electrical current.\n4. The higher the concentration of ions, the greater is the conductance of \nthe solution.\n5. There is a complication however, the water and / or certain of the ions \nmay undergo a chemical reaction to one or the other, or both of the electrodes.\nYou may not want to introduce this in the beginning but it does happen.\n6. None of the ion electrical current carriers of salts dissolved in water \nare as mobile as "free" electrons in a metal are. And the differences are very\nlarge. For example, if the conductivity of  VERY PURE WATER is 0.000004\nconductivity units, the conductivity of a saturated solution of common\ntable salt NaCl is 23 conductivity units, and the conductivity of a typical\nmetal such as copper wire is 60, 000, 000 conductivity units. So while the\nions in a dissolved salt behave something like "free" electrons, they are\nvery slow and sluggish moving. \nCompletely demineralized water actually does not conduct electricity, and is\nwidely used as a coolant in high powered radio amplifiers.  However, when\nexposed to even small amounts of impurities, (even normal air), It becomes a\nfair conductor.  It is not the water conducting this electricity so much as\nthe dissolved minerals in it.  Some of these minerals are decent insulators\nthemselves, but when dissolved in water still allow conduction because the\nmolecules are now free to move around.\nIn ionic liquids these electrons remain \nstuck to big, round atoms,\nand these atoms do the swimming around, relatively slowly, dragged by \ntheir electric charge.\nSort of a ball and chain thing.\nElectrons in metal are "free"; they slip rather freely across all the \natoms, and do not need to drag one around with them.\nSo, carrier mobilities in ionic liquids are some orders of magnitude lower \nthan carrier mobilities in metals.\nSo their resistance is higher.\nIf you had a snail-trail of salt-water or molten salt with the same length \nand cross-section as a metal wire,\nit would use up half the voltage and get hot trying to pass one tenth the \ncurrent the wire can handle.\nIn a metal, each metal atom contributes about one mobile electron that \nhelps the current flow.\nIn molten salts like NaCl, every atom has a + or - charge and contributes \nto the current flow.\nSo there are just as many carriers per unit volume as in a metal.\nBut in water-solutions of salts, the salt is a minority.\nUsually less than 10%  of the solution is ions, so that makes the \nconductivity even poorer.\nThat is part of why we will never make our power lines out of seawater in \npipes.
1005012
Maybe it has something to do with grounding. If a ship is in the ocean and not touch anything then there is no reason for the current to go up right?
619191
It would definitely effect the field and the result would  be vector addition. If the source (here current) is supposed to generate a constant electric field then current gets effected but if there is no constraint then there is no reason for current to change.
179510
The lines of force produced by the electrons in a magnetic field are like the wake produced by a boat. When that wake encounters another boat it will push it along in the water. Likewise when lines of force in a moving magnetic field encounter electrons it will push them. So the magnetic field produced by current flow in a wire can induce current flow in another wire.
1115026
Voltage is simply the potential electrical "pressure" of a circuit.  Current is the actual flow of electrons, so that's what's felt.  Think of it in terms of water & pipes.  You feel the water flow, not the potential pressure behind it.  If there is more resistance (smaller pipes, more valves), the potential pressure of the water doesn't change, but the flow is reduced.
100152
Reasons for currents\nSurface ocean currents are generally wind driven and develop their typical clockwise spirals in the northern hemisphere and counter-clockwise rotation in the southern hemisphere due to the imposed wind stresses. In wind driven currents the Ekman spiral effect results in the currents flowing at an angle to the driving winds. The areas of surface ocean currents move somewhat with the seasons, this is most notable in equatorial currents.\n\nDeep ocean currents are driven by density and temperature gradients. Thermohaline circulation, also known as the ocean's conveyor belt, refers to the deep ocean density-driven ocean basin currents. These currents that flow under the surface of the ocean, and are thus hidden from immediate detection, are called submarine rivers. These are currently being researched by floating devices, which maintain their depth according to slightly differing densities of waters. Upwelling and downwelling areas in the oceans are areas, where significant vertical movement of ocean water is observed.\n\nSee also:  http://en.wikipedia.org/wiki/Hydrothermal_circulation & http://en.wikipedia.org/wiki/Thermohaline_circulation
649175
are you trying to suggest that time travel in the reverse direction,ie, travelling to the past, is possible..\n\nif thats the case then anything can have an opposite of it, like mass etc. which are conventionally taken to be positive
703775
Yes , it is. And this from at least two view points:\n1) The salty marine water is a full of ions, so it represents  very clearly a electrolyte which is a conductive solution. All you need then is some electrodes which should have some differential potential in electronegativity. \n\n2)  The power of the waves which, there are already used as one of the alternative power producing  method. This is used either by actuating some radial turbines, or indirectly some kind of pistons actuated by some floating devices found on the surface of the water, in relative axial motion with respect to the fixed body of the piston. All of this devices are using the power of waves to actuate, then  directly, the generators. \n\nGood luck \nDfriend :)
1102874
You are referring to something called the "Coriolis effect".\nAlthough the Coriolis effect is indeed real, it is a very weak force in reality and does not practically influence the direction a liquid will drain in a toilet.\nThe water in the toilet will drain in the direction it is induced to, the Coriolis effect is totally negligible in this case since it is so weak when compared to the many other forces acting on the water.