Voltage is the unit of measurement for electronic potential, from one point location to another.

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Why does voltage remains same over Parallel Circuit

Why does voltage remains same over parallel circuit. If a resistor is connected in the circuit some of the charge should be transformed into heat and make a lack of charge after the resistor (in my ...
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2answers
550 views

Why does vaccum have a nonzero characteristic impedance towards electromagnetic radiation

OK, so the characteristic impedance is calculated "as square root of the ratio of the permeability of free space (µ o ) in henrys per meter ( H/m ) to the permittivity of free space ( o ) in farads ...
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1answer
94 views

Why isn't this working? [closed]

I just broke a 120mm computer fan in name of science and now I'm pissed; can anyone explain why this doesn't work? : The battery should create a potential difference across the motor, causing the ...
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2answers
183 views

Why doesn't Bernoulli's Principle apply to Current and Resistors in a circuit?

Bernoulli's principle makes sense when you apply it to fluids. If you decrease the diameter of a pipe then the velocity of the fluid increases because it needs to keep the same rate of fluid moving ...
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3answers
212 views

Potentiometer voltage change

I'm trying to understand simple things about electricity reading allaboutcircuits.com web. This chapter includes image which´s principle I don't understand. Here it is: When supplying constant ...
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1answer
3k views

Why is Energy = Voltage x Charge, and how to prove that?

As you know the equation $\mathbf{E=V\times Q}$. Where: $\mathbf E$ is the energy measured in joules, $\mathbf V$ is potential difference (Voltage), $\mathbf Q$ is the charge. So my qustion is: ...
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4answers
675 views

If components of differing resistance are wired in parallel, how does a common voltage drop arise?

I've been teaching myself DC electronics as a hobby and, although I have a feeling i'm "missing something obvious", I was wondering if someone could help me out. If two components of differing ...
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1answer
316 views

Electric power for current density

The electric power produced by a current $I\in\mathbb{R}^+$ and a voltage $V\in\mathbb{R}^+$ is $$ P = IV. $$ Now the current is given as an (alternating) current density ...
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5answers
724 views

Difference between ways of transmitting power

There are two ways to transmit the same amount of power, 1 amp at 1 million volts or 1 million amps at 1 volt. Conceptually what is the difference? How can I think about it conceptually? I would ...
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1answer
67 views

Would the empirical behavior of a simple circuit match my model of it?

I have a practical problem in E&M which has baffled me and and my electrician. The copper water pipes in my house are carrying a current of small potential (~1V) AC current. Here is my ...
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0answers
106 views

About electric current analogy

my teacher gave me this analogy to the electric current , the wire is like a pearl necklace where the pearls can move, the current or the movement of electrons is like putting your fingers between 2 ...
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3answers
358 views

Which quantity gives the resistance of a component?

In a current vs potential difference graph, we can obtain the value of the resistance of the component. There are books that say gradient-inverse is the resistance and also books that say the value of ...
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2answers
385 views

How to find $\tau$ in this circuit?

1) 2) I know, that $$ τ = \frac{L}{R} $$ but what is $R$ in this formula? It seems to be the total resistance, but how to find it in 1) and 2)?
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4answers
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Potential Difference Between Capacitors in Series

I am struggling to find an answer to this, hopefully relatively simple, question. I had a search on stackexchange but couldn't find anything helpful. We are learning about capacitors in Physics and I ...
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2answers
5k views

What happens when non-equal voltages are put in parallel? [duplicate]

If two batteries, say 2 volts and 5 volts, are connected in parallel, are there any problems? The higher voltage will then want to flow out, but also towards the lower 2 volt battery end, right?
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2answers
130 views

Electric power transmission

If we want to transmit electic current for a long distance, we must minimize a heat that releases because of the resistanse. We cannot make a cable wide because it is expensive and it will be massive. ...
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1answer
96 views

Help Understanding Non-conservative Fields

While watching a video lecture, I became uncomfortable with the results, (around 35 mins). The professor draws an electric circuit with a 1V batter, and two resistors (1 and 9 ohms). He then ...
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1answer
3k views

Volts, Amps, and Practical Electrical Knowledge [duplicate]

I've heard people say that high amperage or high voltage is dangerous to humans-aren't they both? And what are the advantages to high amperage versus high voltage? And how do you generate one or the ...
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3answers
4k views

Why does the area of the plates affect the capacitance?

Why does the area of the plates affect the capacitance? Lets say I have a parallel plate capacitor with a charge of 10C and a potential difference of 5V. By the definition $C=Q/V$, the capacitance is ...
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2answers
230 views

About the electrostatic voltage

What's the difference between electrostatic voltage and normal voltage, like the battery's voltage. How to calculate the charge on a charged plate if we knew its electrostatic voltage?
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59 views

What works on 8-10 volts, 4 milli amps, and is not hardwired? [closed]

I want to know what is the smallest device that can work on a few milli amps? I know a NE-2 neon bulb works on less than 10 mAmp but on 90 volts at least. I need to find a small device that: 1- ...
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1answer
2k views

How electrons act under rotating magnetic field?

I study Power Engineering in University. Today I asked my lecturer to explain me exactly how atom's electrons act under spinning rotor's magnetic field, that generated dynamic electricity. But he even ...
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1answer
610 views

Calculate Capacitance in Series AC Circuits?

I'm supposed to calculate the capacitance of an unknown capacitor in series, but I'm not sure exactly which equation to use. I know the voltage across the resistor (Vr), voltage across the capacitor ...
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2answers
455 views

Out of phase voltage current source and resulting power

Examining the following graph, I am trying to understand the power plot. The power appears to take on a negative value when the current changes direction or the voltage changes polarity. Negative ...
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1answer
153 views

Should the electric potential of a positively charged sphere be negative?

Because the indefinite integral of the electric field results in a negative value? (As the function is proportional to $r^{-2}$? I've got to be missing something... Help please!! Thanks! Also, I ...
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1answer
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Electron volt and Voltage

Voltage is the work done per unit charge. Given by: V = W/q Electron volt is the maximum kinetic energy gained by the electron in falling through a potential difference of 1 volt. Given by: K.E ...
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I don't understand what we really mean by voltage drop

This post is my best effort to seek assistance on a topic which is quite vague to me, so that I am struggling to formulate my questions. I hope that someone will be able to figure out what it is I'm ...
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1answer
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Relationship between resistance and voltage drop

In a series or parallel circuit, if two bulbs have the same resistance, do they have the same voltage drops? The problem I am asking about is below. Do A, B, and C have the same voltage drops since ...
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4answers
345 views

Why is there a potential difference?

The question then asks for the potential difference between $X$ and $Y$, which is claimed to be $3.6\text{ volts}%$. Why would there be a potential difference in this case? If I connect a lightbulb ...
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1answer
103 views

Which of these two methods is correct for calculating current?

I recently came across a question, for which I saw two possible methods of finding the solution. I was required to calculate the "current flowing" $I$ when given the voltage $V$, frequency $f$, total ...
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6answers
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Is voltage electric potential or electric potential difference?

On Wikipedia, voltage is defined to be the electric potential difference. However, I am still not certain as to whether voltage is the electric potential ($PE/q$) or electric potential change ...
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Why is electric potential scalar?

I can't conceptually visualize why it would be so. Say you have two point charges of equal charge and a point right in the middle of them. The potential of that charge, mathematically, is proportional ...
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2answers
1k views

How does the voltage between two charged sheets change if change their distance

Suppose I have two charged capacitor plates that both are isolated and carry a charge density $D = \frac QA$. According to textbook physics the electric field between them is given by $E=\frac D ...
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Current without Voltage and Voltage without Current?

At school I've always learned that you can view Current and Voltage like this: The current is the flow of charge per second and the Voltage is how badly the current 'wants' to flow. But I'm having ...
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51 views

Question about linacs

Why are the electrodes of a linac connected to an alternating voltage? Within an electrode the electron moves with a constant speed, and once it is outside of the electrode it accelerates uniformly, ...
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1answer
607 views

What kills you: Voltage or Electric current? [duplicate]

Possible Duplicate: What causes an electric shock - Current or Voltage? When someone gets electrocuted, what kills them; a high Voltage or a high Electric current, and why?
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1answer
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What is the role of battery across a Parallel plate capacitor having equal charge?

Each plate of a parallel plate capacitor has a charge $q$ on it. The capacitor is now connected to a battery. Now, which of the following options are correct? a) The facing surfaces of the ...
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2answers
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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?
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1answer
358 views

What does the current vs voltage graph of a halogen look like?

I have a halogen light with a tungsten filament. It is rated 500w at 130v but I am running it from an inverter in my car that is putting out 110v. I would like to know what the actual power usage of ...
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1answer
2k views

Effective resistance of inductor

In a lab experiment, we connected a simple circuit: an AC voltage source, connected (in series) to a variable resistor and an inductor. We measured the current in the circuit, and the voltage that ...
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1answer
457 views

Elastic collisions in Franck-Hertz experiment

Looking at a Franck-Hertz experimental setup, and given a potential difference such as $4.0\ V$ which is too small to excite out the first electron orbital, the electrons moving through the tube will ...
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2answers
95 views

Production of electricity from atmosphere

I read the electric field intesity at the surface of earth is 100v/m. Then why can't we keep two metallic sheets at different heights and produce a continuous current by connecting these two sheets ...
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1answer
699 views

How do I solve the current of this resistor using Maxwell's Current Theorem?

I've been trying to solve this using the method the prof. taught us, and I happen to know the answer but I can't reach it no matter how many times I've tried. The circuit in question is below: I am ...
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2answers
95 views

Minimal voltage in linear accelerators to achieve relativity?

Could anyone tell me what is the minimal voltage between anode and cathode in a linear accelerators to achieve speeds where relativity starts to show? Let me ask in a different way: "What is the ...
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2answers
755 views

Highest man-made voltage

What was the highest voltage achieved and was it produced by electrostatic means or just some transformers and multipliers? What are the limitations when it comes to producing voltage using ...
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1answer
212 views

About voltage and charge of van de graff generator

I have read that in case of Van de graff generator $V=kQ/r$ where $r$ is radius of the sphere. If that's the case, does the same voltage results in bigger charges in bigger radii?
3
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1answer
694 views

Calculating the electric relative permittivity of fluid or medium?

I'm unsure of how to calculate the permittivity of a fluid. Permittivity differs from one fluid to another: $$\varepsilon=\varepsilon_r\varepsilon_0$$ Since it is an electrical property combined ...
6
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2answers
1k views

How electric currents can flow between 2 points at the same potential?

According to Ohm's law, if there is a potential difference, $V$, across a resistor then there is a current, $I$, flowing through it. Since we assume that points along the connecting wire are at the ...
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1answer
69 views

Charge of an electrolytic capacitors

I can't understand the electrolytic capacitors, when a capacitor has a capacitance of 100 microfarads, does that mean that when it is charged with 100 volts will the charge of the plate be 0.01 ...
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2answers
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Confusion about P=VI and V=IR

If we look at $P=VI$, we see that if the current doubles then the potential difference is halved but this doesn't seem to make sense according to $V=IR$. If we look at that equation, since the ...