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Voltage = Energy/ Charge

If voltage comes out of the negative terminal through a wire to do the powering and then end up at the positive terminal, then what is it that comes out the positive terminal.

current.

all right so whats current.

current is coulombs.

then whats coulombs.

coulombs are electrons with charge.

Question: How could coulombs of electrons with charge come out of the positive terminal as electric current if they are suppose to come out of the negative terminal?

If anyone could help with this by shedding some insight or answering the last sentence above instead of just DOWNVOTING, you might be at risk of being the better person. Instead of acting like some stuck up brainiack snob.

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closed as unclear what you're asking by ACuriousMind, Colin McFaul, Gert, John Rennie, CuriousOne Mar 24 '16 at 8:25

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Nothing comes out: electrons go into it. $\endgroup$ – tfb Mar 23 '16 at 21:58
  • $\begingroup$ @tfb that was helpful. $\endgroup$ – Max R. Mar 24 '16 at 3:37
  • $\begingroup$ as far as your last sentence, note that I=dQ/dt (en.wikipedia.org/wiki/Electric_current#Metals ) . It is convention. If a direction is given to I, the positive charge moves in the direction of I the negative against it. $\endgroup$ – anna v Mar 24 '16 at 4:41
  • $\begingroup$ I just want to thank all those here who gave their time and sincere effort to trying to answer or help this poor question. To all those who just bitterly down voted and put my question on hold, you know who you are, your not worth writing about any longer. @Qmechanic I appreciate your edits. $\endgroup$ – Max R. Mar 24 '16 at 18:07
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If voltage comes out of the negative terminal

Voltage is an across variable, not a flow variable; voltage does not 'come out' of a terminal.

then what is it that comes out the positive terminal.

current.

If power is delivered to the circuit element, the electric (not electron) current is in to the more positive terminal. If power is supplied by the circuit element, the current is out of the more positive terminal.

all right so whats current.

(Electric) current is a flow of electric charge.

current is coulombs.

(Electric) current is a flow of electric charge.

then whats coulombs.

The Coulomb is the unit for the amount of electric charge.

coulombs are electrons with charge.

The Coulomb is the unit for the amount of electric charge. There are no electrons without charge.

How could coulombs of electrons with charge come out of the positive terminal as electric current if they are suppose to come out of the negative terminal.

Electrons have negative electric charge and thus flow in the direction opposite to the direction of electric current (electron current direction is opposite to electric current direction).

If electrons exit the more positive terminal, the electric current enters the more positive terminal and, thus, the circuit element is being supplied power, e.g., a resistor.

However, for a battery supplying power to a load, the electrons exit the more negative terminal of the battery.

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  • $\begingroup$ @ Alfred." (electron current direction is opposite to electric current direction)." what! how could that be if the electron current is the one taking charge through the wire to the element making it WORK . " $\endgroup$ – Max R. Mar 24 '16 at 3:26
  • $\begingroup$ @MacR. see the answer here quora.com/… $\endgroup$ – anna v Mar 24 '16 at 4:26
  • $\begingroup$ @MacR. electron current is the flow of electrons, a flow of objects which have the property of being electrically charged. Electric current, in contrast, is the flow of electric charge without regard to the entities that 'carry' it. While it is true that electrons are the mobile charge carriers in metal, consider the charge carriers in, for example, an electrolyte within a battery. In that case, you might find that both positively and negatively charged ions flow (in opposite directions) and yet, there is just one electric current and it is in the direction of positive charge flow. $\endgroup$ – Alfred Centauri Mar 24 '16 at 18:04
  • $\begingroup$ @ Alfred " Electric current, in contrast, is the flow of electric charge without regard to the entities that 'carry' it. " I feel that is like saying a car driving on the freeway empty and with no driver. " there is just one electric current and it is in the direction of positive charge flow. " would that positive charge flow happen to be on the electrons or protons. $\endgroup$ – Max R. Mar 24 '16 at 18:17
  • $\begingroup$ @MacR., (1) your question makes no sense to me and (2) I'm not interested in working this out with you in this comment section. $\endgroup$ – Alfred Centauri Mar 24 '16 at 19:06
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Before I answer your question, let's start with correcting your first statements. First of all: voltage does not "come out of" the battery. The voltage is a scalar field which represents the electrical potential energy per unit charge. It has a certain value at every point in space. It is not a physical thing that is moving out of the battery.

Next, current is not measured in Coulombs, it is measured in Amperes: a current of 1 Ampere means 1 Coulomb of charge is passing by in 1 second.

As for your question, I believe what you're confused by is the difference between the direction of the electric current, and the direction of movement of the electrons. In your battery example, what is actually flowing is the electrons. However, the convention is that we assign to electrons a negative charge. Because the electric current is defined as the direction of flow of positive charge, the direction of the electric current opposes that of the actual electron flow.

This sometimes confusing convention seems to originate from Benjamin Franklin, see for example: http://www-spof.gsfc.nasa.gov/Education/woppos.html

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  • $\begingroup$ appreciate your answer. but " Because the electric current is defined as the direction of flow of positive charge, " how could that be if the NEGATIVE electrons "shooting/bumping" out of the negative terminal through the wire is the one with CHARGE. $\endgroup$ – Max R. Mar 24 '16 at 3:36
  • $\begingroup$ @MacR. Again, it is just a matter of convention. Benjamin Franklin did not know about the existence of electrons. He found that when you rub certain materials together, each of them becomes charged (now known as the tribo-electric effect) . He then (pretty much arbitrarily) called one of them positively charged and the other negatively charged, and postulated that the current runs form + to -. Over a century later, electrons were discovered. These were found to be responsible for the electric current, and they run from (Franklin's) - to +. $\endgroup$ – Jeff Mar 24 '16 at 11:54
  • $\begingroup$ " Over a century later, ELECTRONS were discovered. THESE were found to be responsible for the ELECTRIC CURRENT, and they run from (Franklin's) - to +. " exactly! Try reading Alfred's last comments and let me know if they match yours. $\endgroup$ – Max R. Mar 24 '16 at 17:04

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