All Questions
27 questions
2
votes
2
answers
95
views
How could free electrons flow in a conductor? If electrons actually flow in a conductor, then won't the atoms of the conductor become unstable?
I've read in many physics books that electrons flow due to a potential difference across a conductor, and that the flow of electrons is opposite to the current direction. But, if electrons move from ...
- 23
1
vote
1
answer
131
views
Galvanic cell - when do we get electric potential?
In the galvanic cell in this image (2nd one with salt bridge): Link
Before putting the copper wire into the solution, do the Zn metal electrons have potential energy with respect to Cu2+'s electric ...
0
votes
0
answers
37
views
The flows of electrons when the voltage is zero [duplicate]
As we understand, electrons can't be unmoving therefore electrons always moving or flowing. If the voltage is zero, where do the electrons move? Do they move everywhere?
- 364
0
votes
1
answer
79
views
What exactly happens in a circuit after it gains potential energy?
When an electron moves across a resistor, it loses potential energy.
Now imagine a simple circuit (series connection) with the negative terminal having 10v as its potential and positive terminal ...
- 87
1
vote
3
answers
1k
views
Does current make the full return trip?
In an AC system, the neutral wire is said to provide a return path for the current back to it's source. Given that the current is said to be alternating back and forth, how does this work, does the ...
- 13
1
vote
2
answers
293
views
Does a higher voltage always mean a higher electric field strength?
In a step-up transformer, the output voltage is higher than the input voltage, while the output current is lower than the input current. Basically, since P = VI is conserved, the current has to ...
- 337
1
vote
4
answers
378
views
Understanding voltage, what is physically happening with the electrons?
The way I understand voltage vs current is that voltage is the potential energy (or force) of the current. And the current is the amount of charged electrons passes through a conductor at a point ...
- 11
1
vote
1
answer
83
views
Is there some relationship between circuit voltage and the speed of circulating electrons?
It is well-known that under an external electric field the work that a charge has to do to go from a point A to another point B is $w=-V_{AB}*q$, this is equal to $\int_A^B{-\nabla V·dl}$ which would ...
- 413
0
votes
1
answer
137
views
Is current (flow of electrons) all about repulsion?
We know that battery produces charge separation between the two terminals by means of some chemical reaction. So now we have negative charge (accumulation of electrons) at negative terminal and ...
- 29
0
votes
2
answers
606
views
Why does the change in the speed of a moving electron not change the current?
If electrons are flowing through a conductor, then we have a current.
During my study, I’ve learnt that increasing the speed of electrons increases the current.
If those electrons pass through some ...
- 11
0
votes
1
answer
27
views
When electrons move regardless of what the voltage is, is the strength of the magnetic field a constant?
When electrons move regardless of the what the voltage is, is the strength of the magnetic field a constant?
My understanding of the ammeter is the magnetic field of the moving electron effectively ...
1
vote
1
answer
2k
views
Drift velocity component of electrons in alternating current
I'm not sure if this question will qualify as cross-posting, but feel free to tell me if it does so that I can delete it. However, this question certainly does relate to both physics and electronics, ...
- 929
1
vote
2
answers
49
views
What is the Electron Flow in a wire with 2 power sources 180 out of phase?
If you took two independent power supplies and set them to a sine with each power 180 degrees out of phase. The powers supplies will share a common line and the load will be equal_____________?
Do ...
- 11
-1
votes
1
answer
144
views
The flow of electric current
If positive charges have higher electric potential difference than negative charges then why the negative charges (electrons) are the one that are moving in a circuit? and to my knowledge the ...
- 1
1
vote
2
answers
93
views
How many volts must an electric current have for the electrons traveling within it to travel 90% the speed of light when going through a vacuum [closed]
How many volts must an electric current have for the electrons traveling within it to travel 90% the speed of light when going through a vacuum, also, what is the mathematical relationship between ...
- 15
2
votes
1
answer
2k
views
Diffusion and Drift currents in forward bias
Why do the current in diode in forward bias configuration called "Diffusion current", even if this current is a resultant of external voltage supply which create electric field in diode, ...
- 53
0
votes
1
answer
246
views
How can the voltage in a circuit possibly be constant for different resistances?
Consider two identical electron battery circuits, Circuit A and Circuit B, with the only difference being the resistance at resistors, which is higher for B than for A. The drift velocity of a given ...
- 505
1
vote
2
answers
1k
views
Why does a fuse blow when connecting to opposite terminals
A fuse "blows" if current greater than fuse's rating flows through. But recently I was connecting battery terminals opposite on a motorbike; this kept blowing the fuse. When I correctly connected the ...
0
votes
0
answers
53
views
What happens if an electrical current has two paths of unequal length?
Suppose I connect one 1 km cable and one 1000 km cable to the same pole of a power source and also connect them together at the other end. Suppose (theoretically) the longer cable has the exact same ...
- 101
7
votes
3
answers
891
views
Voltage as electromotive "force"
Considering the "water analogy" for electricity, it seems voltage is sort of like gravity:
(image source: http://learn.olympiacircuits.com/electricity-flows-like-water.html)
Now when water actually ...
- 370
3
votes
3
answers
876
views
How do the electrons "know" where to go when grounded in this simple lightbulb example?
A rookie question but I'm reading a chapter in a book (Code: The Hidden Language of Computer Hardware and Software) that discusses a simple electricity/lightbulb model (pictured below)
The book says ...
- 33
0
votes
4
answers
10k
views
Electrons moving in a simple circuit with a battery and a light bulb
I believe my understanding of electric currents is flawed and want some help to clear up a few things. I'm not looking for a precise scientific understanding, but to understand the basics. I'll try to ...
- 319
0
votes
2
answers
1k
views
Is the electric field in the wires of the parallel circuit always the same and how that affects current?
When we connect two resistors connected in parallel with a battery, it creates an electric field through this wire.
well, my question here:
Is the electric field in the main wire is the same as the ...
- 756
0
votes
1
answer
158
views
Voltage and Current
I know that as voltage increases, current increases by $V=IR$, but I really find some difficulty in understanding this at the atomic level (what happens with the electrons inside that wire). I ...
- 756
1
vote
2
answers
249
views
Current due to External Electric Field
Assume a conductor in a rectangle shape for simplicity.
Now, if I only choose one side of this rectangle having length L, and apply external electrical field ∑ only to it(along with the wire), what ...
- 563
10
votes
2
answers
17k
views
What creates voltage? What causes electrons to move in a wire?
I was trying to break down how a transistor works to a friend, and I took a moment to think about electric current and voltages. I realised I do not understand where these phenomena come from. I ...
- 203
0
votes
2
answers
359
views
Is it possible for electrons to carry more than one charge?
Sorry if this has been asked before. Could also be a really basic question (new to electrical study).
I am a bit confused about the relationship between electrons and charges. So what I understand is ...
- 103