Questions tagged [electron]

Anything related to the behavior and properties of electrons, i.e. the elementary subatomic particles accounting for electrical conduction in most solid materials, especially metals.

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12answers
20k views

Is voltage the speed of electrons?

Current is the amount of electrons passing through a wire. Can we say that voltage is the speed of those electrons?
19
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9answers
23k views

How is the internet able to transmit data so fast?

I'm not sure if I'm in the right place or not, but I figured someone here could maybe provide a good answer. I want to know how electricity is able to flow so fast. For example videos games nowadays, ...
12
votes
3answers
23k views

How does data travel inside a wire?

I know this is a very basic question but the answers returned by google are way too complicated for me to understand. I am not asking about modulation here. What I want to know is what exactly is ...
10
votes
4answers
2k views

Does current flow on an open transmission line?

Please take a moment to look at the diagram below: The question is if the lightbulb will momentarily flash when the switch is closed. I think it will but I get the feeling I am wrong. The reason why ...
10
votes
4answers
4k views

Flow of holes in transistor?

Bipolar transistor are said to have both electron flow and hole flow. Movement of electrons can be understood, but holes are fixed part of the atomic/crystal structure. How can we characterize their ...
9
votes
3answers
2k views

Flow of electrons in a wire

Electricity is "flow of electrons". My child asked me if this is so, then ultimately the copper wire should disappear/vanish/finish because the matter is moving from one place to the other. I am not ...
8
votes
4answers
1k views

Free Electron in Current

An electric current is a flow of free electrons. Are these free electrons totally free from the orbits of metal atom or they moving by jumping from one orbit to another orbit of the atoms? If they ...
7
votes
7answers
3k views

Transistor - Why does amplification happen before the transistor and not after?

I know this is a noob question but I just can't find an answer for it on google search results. Well my question is basically this: How come the amplifying occurs before the transistor [red line] and ...
7
votes
4answers
5k views

Antistatic mat , how it works?

I have a large anti-static mat lying on the table of my workdesk, which looks like this. And it's connected to ground through the wall outlet from one point, meaning it's an open-loop: Let's say I ...
6
votes
3answers
744 views

How do electrons carry thermal energy in Peltier coolers?

I've read that when electrons enter from metal to semiconductor type N, they gain thermal energy and make that side cooler and the reverse happens when they leave semiconductor to the conductor. Why ...
5
votes
3answers
192 views

How does current turn to heat/light? [duplicate]

When resistors are serially connected, the current is the same through the whole circuit. To my knowledge, the electric current is electrons traveling. Also, the power of the generator equals the ...
4
votes
2answers
929 views

Protons and DC circuit

In a metal wire, do protons flow in the opposite direction from the positive terminal, like electrons do from the negative terminal towards the positive terminal?
3
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2answers
417 views

A question about electrons, charges and current

Let's talk about DC, a very simple circuit: a light bulb and a battery. Some authors say that electrons move from negative to positive and current from positive from negative. I always thought ...
3
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3answers
2k views

So which direction do electrons really flow?

As I understand it, electrons (which are negatively charged) flow towards positive. As a convention, we say that current flows from positive to negative. Is this to say that what you connect the ...
3
votes
4answers
3k views

Does the resistor have to be before or after the component [duplicate]

I am an electronics beginner and I created a small little circuit, just a battery a resistor and a led, then to ground. This is the circuit: simulate this circuit – Schematic created using ...
3
votes
4answers
2k views

Does free electrons from the conductor itself flow or electrons inside the battery flow?

I am new to electronics. I read electricity works this way: some atoms have more electrons than protons. These free electrons flow through a conductor such as a copper wire. However, to induce flow of ...
3
votes
2answers
166 views

Electron Flow Confusion

Using conventional notation in the diagram below, I understand that the circuit is not complete because the diode is in reverse bias. But knowing that the electrons actually flow from the negative to ...
3
votes
2answers
361 views

How does an electron beam move in XY mode?

I was recently observing some Lissajous figures on an analog scope in XY mode . I was wondering how does the electron beam move . I know it should move from left to right but I find it difficult to ...
3
votes
2answers
377 views

Why is electron flow taught in some contexts? [closed]

The standard as I learned it is that the flow of current is from positive voltage to negative voltage. The direction of current flow is opposite the direction of electron flow. This is what I learned ...
3
votes
0answers
287 views

How is it that two electric currents can travel in opposite directions on the same wire, at the same time, without interfering with each other? [duplicate]

An Introduction to Information Theory: Symbols, Signals and Noise, by John R. Pierce, says the following: While linearity is a truly astonishing property of nature, it is by no means a rare one. ...
2
votes
2answers
110 views

At what acceleration will electron flow be disturbed?

Came across a question regarding max G force that electronics can withstand, and immediately wondered at what speed/force will the electron flow be disturbed, and/or stopped. I might not be thinking ...
2
votes
1answer
226 views

Is there a limit on the charge that can flow in a wire?

I assume when I hook up a 12V battery to a wire, all the free electrons in the wire move. If I hook up 24V, they move faster so more charge passes a area cross section for i=C/s. But in AC, their ...
2
votes
2answers
4k views

Why is CMOS fall time faster than rise time?

I've just started a computer architecture class, and the slides from a lecture says that the reason why fall time is faster than rise time is that the NMOS electrons have more mobility than PMOS which ...
2
votes
2answers
197 views

Why do electrons move as if on conveyor belt in a circuit?

For example sometimes people will ask whether it matters what side of a component you place a resistor on. Surprisingly, it doesn't matter because electrons behave as if they're all connected together ...
2
votes
1answer
107 views

Why is there no shot noise in conducting wires?

Why is there no shot noise in conducting wires, while it is present in junctions and barriers like PN junction? Is electron flow not quantized in wires? If it is, why do a resistor and perfectly ...
2
votes
6answers
2k views

Can vacuum be used to store flowing electrons?

Since electricity can flow through vacuum can it also be used to store electricity? Though it wont remain a vacuum in strictest form.
2
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2answers
403 views

Number of electron with a current of 1A

i'm reading a book that it says : If a current of 1A flows through a copper wire, the number of electrons flowing by a cross section of the wire in 1s is equal to : 1A=(1C/1s)(electron/-1.602*...
2
votes
3answers
130 views

Why the earth attracts charge and where does the charge go when it goes into ground?

Self-explanatory question but to add what I know, by this I will also know if I am right or wrong. I read somewhere that Earth is positively charged, but is not the state (whether positive/negative) ...
2
votes
0answers
351 views

Semiconductor physics, effective mass calculations, band edge. vs. DOS vs cyclotron resonance

I am trying to understand effective mass for electron carriers in the conduction band as found in experiments. I am using the equations in a simulator. The simulator models power mosfets from -85C to ...
1
vote
6answers
4k views

Why do electrons flow from a lower potential energy to a higher potential energy?

So I understand that the term "voltage" refers to the potential energy difference between two points. So, in a 5v battery, there is a 5v difference between the positive and negative ends. When these ...
1
vote
2answers
910 views

If an electron has 0 electric potential after passing through a resistor, how does it flow to the other terminal

If an electrical circuit only contains 1 resistor, and electron's potential difference (voltage) before and after passing through a resistor is equal to the e.m.f, how does the electron have potential ...
1
vote
3answers
522 views

Electron flow at the immediate start of this flip-flop circuit?

I am attaching the following image of a flip-flop circuit. I find myself constantly trying to visualise what is occurring at the exact moment the circuit is closed, and the current starts (electron ...
1
vote
3answers
146 views

is there any impact of Electron's spin in CRT?

fact-1. Electron's (or any-other particles) magnetic behavior depends upon mass, charge and spin. fact-2. All electrons are not the same. Though all electron have the same mass and charge; an ...
1
vote
3answers
502 views

What happens to a DC current at the end of a wire?

This question might be a little more appropriate for the physics stack, but I'd like to test the water here first. I am just getting into electrical engineering, and as I go along, certain aspects ...
1
vote
1answer
214 views

conventional current flow and ground plane

I'm a student. I cant understand why we design ground planes to have a easy (low resistance) path for return current..... If the real flow of electrons is from battery (-) to battery (+) we should ...
1
vote
6answers
7k views

positive vs negative, power vs ground, flow direction

I'm getting very confused about the inconsistency where some people say ground is always negative, and some say ground is always positive. And some would say, electrons travel from the power source ...
1
vote
2answers
95 views

Will electrons be taken from a metal plate if a positive charge is applied to it?

If I have a single metal plate, a battery, and one wire. If I connect the wire to the positive on the battery to the metal plate, does that remove electrons from the metal plate? I am attempting to ...
1
vote
3answers
254 views

Electromagnetic waves [closed]

I have a problem to understand how electromagnetic waves works. Why do transistors create EM waves when they're switching? And difference between antenna and transformer with secondary coil. When I ...
1
vote
2answers
578 views

Meaning of applied voltage on electron

Does the applied voltage create a force on electrons to make them move? I have read that electric field is force per charge. Now, metals have free electrons, so applying a voltage will cause these ...
1
vote
1answer
29 views

Thermal generation of electron-hole couples and reverse biasing

I'm studying the PN junction and I have some problems figuring out thermal generation of couples electron-hole in reverse biasing. The analysis is the standard one (for example, one can find it in the ...
1
vote
1answer
92 views

Confused about current flow

I am starting to learn about electronics and I am still confused about current flow. Initially the book would try to be clear about the distinction between conventional and actual flow but then ...
1
vote
1answer
2k views

How do laser printers produce the positive and negative charges on the paper?

I understand the general idea of how it works but I am a little confused on the actual details. For instance I understand that the corona wire positively charges the entire drum and the laser then ...
1
vote
3answers
169 views

PN junction diode's free electrons

When we look at the PN junction diode, there is always a depletion region, for which one side in negative and one side positive. The reason behind this is that the N side depletion region is ...
1
vote
1answer
107 views

When do the holes in semiconductor appear?

I'm trying to understand the concept of semiconductors, as far as I know whenever an electron moves it leaves a hole, so how can we say (for example) that n-type semiconductor has a majority of \$e^-\$...
0
votes
2answers
161 views

Why is conventional current still taught in school when it is unreal, given that real current flow is electron flow? [duplicate]

Conventional current as a concept is easily understood until the professor says what actually takes place is electron flow. Electron flow moves in the opposite direction as conventional current. Why ...
0
votes
2answers
197 views

Raspberry Pi: Do the electrons flow from the power pins or ground? [closed]

I'm rather new to this and am slightly confused about which direction the electrons actually flow. Using an LED with the knowledge that conventional current flows out of the cathode, and hence the ...
0
votes
3answers
737 views

I want to learn how to make a CPU from scratch [closed]

I am new to electronics, I program from time to time and i know the basics of the logic gates. I have used logisim in the past and I was just wondering if someone could tell me about a good online ...
0
votes
3answers
157 views

How can an electron have 0 electric potential after exiting a resistor but have current?

Unfortunately, I am not able to respond and ask a question on this specific post so I am going to ask a question based on the answers of the user "Transistor" in this post because I am still confused. ...
0
votes
3answers
330 views

Why does current have to return to its source in a circuit?

As far as I know there should be a current when a high potential point is connected to a low potential point, but apparently that is not true. I understand that a circuit must be closed in order for ...
0
votes
2answers
152 views

Where do electrons go after reaching GND in this Arduino Mega design?

When examining the EAGLE file for the Arduino Mega that I downloaded from their official website, I noticed that the ground (GND) is not connected to anything other than the C4 component, which means ...