All Questions
42 questions
0
votes
3
answers
65
views
Why is a powersource characterized by voltage?
Why is it that powersources are characterized by their voltage? If we are given a power source with a certain voltage we know that the potential difference per charge will be constant, and it will be ...
- 199
4
votes
4
answers
3k
views
How does Neutral Wire has lower potential than Live Wire?
This is my current(and most probably very incorrect) picture of how electricity comes in my house.
What I think of this picture is that, the transformer produces current in my house circuit (by ...
- 1,306
0
votes
1
answer
93
views
Why can we talk of electric potential under AC?
An electric potential $V$ is defined by the relation $E = - \nabla{V}$. The existence of such a potential is true in electrostatic (constant electro-magnetic field) because of the Maxwell-Faraday ...
- 294
0
votes
3
answers
423
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What exactly is electric potential? [duplicate]
My book says:
When a small positive test charge is placed in the electric field due to another charge, it experiences a force. So work has to be done on the positive test charge to move it against ...
- 371
0
votes
2
answers
357
views
Voltmeter connected to parallel circuit
This is my current understanding. Voltage is defined to be the potential difference between 2 points, hence it only makes sense for a voltmeter to be connected in parallel. But why must this voltmeter ...
0
votes
3
answers
1k
views
How does current actually flow in a wire?
When I was in my school I was taught that the electric field due to the battery is along the wire (from $A \rightarrow B \rightarrow C \rightarrow D $) and these are responsible for electrons at each ...
- 8,476
4
votes
4
answers
1k
views
What is the difference between electrostatic and electric potential?
What is the difference between electrostatic and electric potential in a circuit?
- 90
0
votes
2
answers
73
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Why don't we know the electric potential at any point in a circuit, only the difference in the electric potential (voltage)?
Why in circuit analysis, don't we know the electric potential at any point in a circuit?
- 90
-2
votes
2
answers
40
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What is the electric potential of each of the 2 points of an alternating current source?
I have that question.
I am not asking about the voltage or electric potential difference.
I guess the answer will depend on what type of generator is used in the power plant: maybe synchronous. Can ...
- 47
0
votes
2
answers
55
views
Can you please help me understand how Electric Potential and Electric Potential Energy work?
Considering the image we observe the following:
$r_A<r_B \Rightarrow \frac{1}{r_B}<\frac{1}{r_A} \Rightarrow \frac{K(+Q)}{r_B}<\frac{K(+Q)}{r_A}$ (if $0<Q$) and thus
$$\frac{K(+Q)}{r_B}=V(...
-1
votes
2
answers
526
views
Electric current and potential difference
I have lots of doubts regarding electrical energy, electric current and voltage. I have tried to understand as much I can but every time I try to completely clear my concept, I encounter a dilemma! So ...
- 499
2
votes
2
answers
476
views
Voltage and Potential in a battery
I would like to think that voltage is like the force provided by the battery to move. When electrons are near the negative terminal of a battery, they experience a repulsive force which makes them ...
- 367
0
votes
2
answers
43
views
Can we say that space without electric field is of 0 potential?
Can we say that a given point in space, without any charges nearby, has no electric field, and thus the electric potential in this point is 0?
- 282
1
vote
4
answers
158
views
Quick question regarding the meaning of Voltage of a Battery
Is the voltage of a battery simply the work necessary to move a unit charge from one extreme of the battery to the other?
If this is the case, then when calculating the voltage of a battery the ...
- 379
0
votes
2
answers
645
views
What does a battery produce? Is it Electric Potential Difference (EPD) or Electro Motive Force (EMF)?
I have read a lot of posts about Electro Motive Force, Electric Potential Difference and their differences, but I still confused. What I know is that EMF produces a EPD and keeps it constant, then ...
3
votes
1
answer
5k
views
What is the difference between electric spark and electric arc?
In my student book they separate these two and indicate that sparks need high voltage to occur while arcs need low voltage with normal or low pressure and electric arcs CAN come with heat and bright ...
- 59
1
vote
2
answers
49
views
Why are voltage and volt both are denoted by $V$? [closed]
Why are voltage and volt both are denoted by $V$? Won't it cause confusion?
1
vote
0
answers
876
views
How does a battery create potential difference? [duplicate]
I'm in year 10 (9th Grade for the Americans) and I just had a question about physics.
How does a battery create potential difference?
It it because the electrons are gaining energy as they get pulled ...
user272011
1
vote
1
answer
53
views
Differences between $V_{ab}$, $\Delta V$, $\Delta V_{ab}$, $\Delta V_a$ and $V_a$
$V$ is electric potential.
From my understanding of these notations
\begin{align}
V_{ab}&=V_a-V_b\\
\Delta V&=\Delta V_{ab}=V_b-V_a;\text{consider $a\to b$}\\
\Delta V_a&=V_a=V_a-V_\infty
\...
- 324
-5
votes
2
answers
123
views
Voltage about potential difference
Can someone explain to me all about potential difference. It is basically taught when teaching about voltage but I want to know all about potential difference.
- 1
5
votes
1
answer
229
views
What does the term 'high voltage' really mean?
This might be a dumb question but i am not so familiar with the word voltage:
What does the textbooks really mean when they say high voltage?. Does that mean:
There are more charges so more voltage, ...
- 366
2
votes
2
answers
280
views
Why doesn't electric potential decrease gradually across a wire?
Let's assume that the resistance of a wire is zero. Now, suppose the wire has a length of 10 m and is connected to a battery with an emf of 10 V. According to my physics textbook, the electric field ...
- 65
0
votes
1
answer
105
views
What's the source of voltage? [duplicate]
I've been told that in a DC circuit with a battery the negative terminal of the battery "pushes" electrons in nearby atom away of it and those by themselves cause electrons in other atoms to move, but ...
- 180
0
votes
1
answer
269
views
Voltage as the work to move from infinity to a point in field
I understand that electric potential is defined as the work needed to move a charge from infinity to a specific point in the field.
However, how does this apply for a field which is limited between ...
- 15
0
votes
3
answers
4k
views
Electric Potential in the Center of a Electric Dipole
I thought the electric potential at point B would be positive because placing a positive charge at point B would cause it to move releasing energy while doing so. The answer key states that the ...
4
votes
1
answer
152
views
Why does a voltaic cell induce an electric force proportional to voltage?
I'm trying to understand the intuition behind Ohm's law (that current is proportional to voltage).
I understand the basics of the Drude model: if the electrons frequently collide and on average reset ...
- 93
1
vote
3
answers
970
views
Why does the potential along a uniform current-carrying wire vary with the distance along it?
Is it because as the electrons move further through the wire they lose more energy due to resistance?
Also, in this context, I believe potential refers to the electric potential energy but I am unsure,...
- 13
0
votes
3
answers
110
views
Summing up very basic terms in basic electricity [closed]
My attempt to define following terms as per my understanding. I am currently at high school.
Electromotive force (EMF): Potential between two terminals when open circuited.
Wikipedia's version of ...
- 11
0
votes
2
answers
2k
views
Potential difference in a non-uniform electric field
Let's say I have two points in a non-uniform electric field and those points have the electric potential 10 V and 5 V. If I then would use a voltmeter to determine the voltage between those points ...
3
votes
6
answers
1k
views
Why do we use electrical potential difference in a circuit instead of electrical potential energy?
When talking about a circuit, why does voltage stand for electrical potential difference equal to $\frac {Work}{q}$ when instead we can use electrical potential energy? Is it because the charge of an ...
- 128
1
vote
2
answers
212
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What physically determines what voltage something has? [closed]
I know that voltage is energy per charge / energy per electron, but since something such as a wall outlet has 120V with a lot of current but a mostly harmless low current Van De Graff generator has ...
- 635
5
votes
1
answer
3k
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Can conductor be charged?
I have a copper conductor. For a while, I apply a voltage of $12kV$ DC from a source. After removing the source, will the conductor stay charged from the source if is not earthed? Will it discharge ...
- 185
-3
votes
3
answers
342
views
What is voltage in a circuit?
What is voltage in a circuit?
I know potential difference is the difference of potential energy of two points in a space affected by an electric field per unit charge.
Why is there voltage in a ...
- 123
1
vote
7
answers
2k
views
What exactly is a "volt"?
What exactly is a volt? So I Studied the chapter "electricity" in the month of April and got introduced to the concept of "volt".
The concept was too unclear for me so I tried to ask some questions ...
- 715
1
vote
2
answers
2k
views
What is the difference between the potential difference and potential energy of an electron?
What is the difference between the potential difference and potential energy of an electron?
Let's take an example the potential difference (PD) across a resistor. if there's a current flowing, the ...
- 527
-4
votes
3
answers
185
views
Doesn't any massive conductor look like "ground" to an AC supply?
I've been puzzling over this excellent answer to the perennial "Why don't I get shocked by a hot wire if I'm not grounded?" question. The orders of magnitude just don't seem right for two reasons:
...
- 924
1
vote
2
answers
241
views
What does it means to say an electric charged person has a higher potential voltage compared to the door?
I'm studying electric potential energy and its defined as the energy needed to move a charge inside an electric field from a point $a$ to $b$. Then, it defines electric potential energy per charge, ...
- 253
0
votes
1
answer
920
views
Is "applying a voltage" the same as "applying a potential" to an electrode?
From what I understand, voltage is the potential difference, but it seems like the terms are used interchangeably. This is confusing me because I am only just learning what these terms mean. I'm also ...
- 147
0
votes
3
answers
4k
views
What does raising voltage do?
If I raise the voltage of a wire from 0V to 1000V and then to 5000V, am I merely packing it with more and more electrons (with those electrons being trapped there until they find a path off the wire)?
- 1,672
8
votes
4
answers
53k
views
How can you have a negative voltage?
How can you have a negative voltage? I don't really understand the concept of negative voltage, how can it exist?
- 97
2
votes
2
answers
423
views
Fundamentality of voltage to current
From Ohm's Law :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points.
I would like to know if ...
- 990
33
votes
12
answers
35k
views
What is the difference between electric potential, electrostatic potential, potential difference (PD), voltage and electromotive force (EMF)?
This is a confused part ever since I started learning electricity. What is the difference between electric potential, electrostatic potential, potential difference (PD), voltage and electromotive ...
- 439