I am a bit confused with the movement of positive charges. I have been told that the positive charges do not move, and the only things that move are electrons. If this is the case, what happens if the positive charge is attracted to a negative charged? Also how does a positive charge move in an electric field?
$\begingroup$
$\endgroup$
1
-
2$\begingroup$ Keep in mind that when you say "positive charges", you are being a bit too general. In metal wires the positive nucleus don't move, no, but in a liquid there can be positive ions moving, in semiconductors positive holes moving, some membranes are designed to only conduct protons (hydrogen ions if you will) etc. There is no rule saying that positive charges don't move while negative charges do - that just happens to be the case in metals. $\endgroup$– SteevenCommented Feb 18, 2017 at 0:05
Add a comment
|
3 Answers
$\begingroup$
$\endgroup$
I have been told that the positive charges do not move, and the only things that move are electrons.
In the vast majority of solid conductors (like metals) this is correct. In other situations, this is not true.
In metals, the atoms are held in place by chemical (electron) bonds. So the nucleus and its positive charge, and most of the electrons are fixed in place. A small proportion of the electrons are free to move though. So an electric field in a metal will cause some electrons to move.
If you had positive charges that weren't bound together (ions in solution, ions in plasma, etc.) then they will move in response to an electric field.
If this is the case, what happens if the positive charge is attracted to a negative charged?
I don't understand this question. Opposite charges do attract each other. But that doesn't mean motion is always possible.
answered Feb 17, 2017 at 23:35
$\begingroup$
$\endgroup$
3
I think there are two situations here. If a positively charged object, like a proton, is in an electric field, it will be pushed by the field and move. On the other hand, in an atom, even though electrons and protons both experience a force toward each other, the electron moves a lot more because it is much, much lighter than the proton.
-
1$\begingroup$ Thanks for the answer but is the reason why a proton doesnt move in atom due to its mass or due to the fact that its located in a nucleus? And for a field, does it being a proton not matter? $\endgroup$– ShrizamvCommented Feb 17, 2017 at 23:12
-
$\begingroup$ @Shrizamv The proton doesn't move because it is much more massive than the electron. Scientists have created atoms with positrons instead of protons: en.wikipedia.org/wiki/Positronium. Since positrons have the same mass as electrons, both particles move equal amounts. As for a field, that's right; all electrically charged objects are pushed by electric fields. $\endgroup$– Mark HCommented Feb 17, 2017 at 23:20
-
$\begingroup$ @MarkH you're correct about plasmas, but not correct in general. Protons move just fine in acid solutions, while the electrons don't move, because in electrolytes there are no free electrons. $\endgroup$– wbeatyCommented Feb 18, 2017 at 4:45
$\begingroup$
$\endgroup$
The question is still not answered although well attempted so let me explain the question in more detail. If there are no positive charges but rather holes that only seem to move but dont actually move & only electrons can move inside conductors, how come the diodes become forward biased & reversed biased in a full wave rectifier? And even how the AC changes polarity at all?
