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

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Voltage of a quadrupole magnet

I have a simple question and it's my first one in this community. :) Does the voltage of a quadrupole magnet depend on the power of the electron beam in a synchrotron? Perhaps someone has a good ...
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1k views

How can be the neutral wire at 0 volts when current flowing through it?

Voltage is potential difference, and current flows because of voltage. So if the voltage is zero, how can current flow through the neutral wire.
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Current flow direction, based off the equipotential line?

From the following diagram: Given the wires are only connected to a certain portion of the conductor, will current flow all around the conductor? Or only throughout the equipotential line(diagram ...
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21 views

Does doping and size determine the characteristics of a semi-conductor?

Does the maximum voltage and current that a semiconductor can withstand (without being damaged) depend upon the size and doping of the semiconductor? If so, then please explain, 1.What is the reason ...
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118 views

Difference in induced current, when magnetic field “span” is reduced?

A conductor of known volume $(V)$ passes a uniform magnetic field$(B)$with a constant velocity $(v)$ the conductor is a source of induced EMF, a power source to a circuit. The induced EMF can be ...
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594 views

If we connect a long wire to a battery, will battery produce more electrons?

I actually have three related questions: An open circuit chemical cell separates charges creating a surplus of electrons on its negative terminus and a shortage of electrons on its positive terminus. ...
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62 views

What happens if I have a square conducting wire being permeated by a magnetic field and the field suddenly disappears?

Suppose there is a square conducting wire in a magnetic field. The two vertical branches will have the same emf, and the two horizontal branches will have 0 emf, resulting in a net emf of zero and ...
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116 views

Can electromagnets repel?

So I saw a video here https://www.youtube.com/watch?v=wzXRFp0DDrU (See the full video first) I don't understand that how is the electromagnet repelling things in the second half of the video? Also ...
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424 views

How power lines use high voltages with a low current?

I've read that power lines use high voltages and low currents to reduce power loss due to resistance. Looking at the formula for power - P = VI So to increase P, you increase V rather than I for ...
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39 views

Is this diagram in my textbook not constructed to scale?

Or am I having an illusion. Clearly, the distance from 6v to 4v is not the same as 4v to 2v. I know it should be based on: $V = k\frac{q}{r}$.
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162 views

Induced EMF, additive to conductor's closed circuit?

Assume the following conductor, with current flowing, powered from a source $S$: Now, I've introduced a magnetic field($B) to the conductor covering a small area of it like so: The change in ...
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5answers
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How can one derive the Ohm's Law?

I am looking for the derivation of the Ohm's Law i.e., V is directly proportional to I. Can someone help me with it?
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79 views

Does voltage depends on the charge present in an element?

Does the voltage depend on the charge present in a battery ? I know in capacitors q=cv. Hence charge present is proportional to voltage. Is it the same in the case of batteries?
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What is the difference between electric 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, potential difference (PD), voltage and electromotive force (EMF)? All of them have ...
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1answer
107 views

Grounding a capacitor

When one of the plates of an isolated capacitor is grounded, does the charge become zero on that plate or just the charge on the outer surface become zero?
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3answers
52 views

Why is resistance across a load the V per I rather than the V per Q?

There is a load that resists the flow of electrons. This causes a voltage drop, meaning it creates a potential difference between the 2 sides of itself. This property, a load creating a voltage drop, ...
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508 views

Could anyone help explain this current voltage graph for an LED in liquid nitrogen?

I've been doing my coursework investigating LEDs at various temperatures and I've come across an interesting phenomenon which nobody I've asked has been able to explain thoroughly - wheras at room ...
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56 views

Is internal resistance relevant in motional EMF?

When a conductor passes a magnetic field and connected to a circuit, the induced voltage is calculated via the motional EMF($\epsilon$): $$\epsilon=-vBL$$ Is the conductor's resistance (or internal ...
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66 views

Why is voltage essential in circuits?

I understand what voltage is, but why is it necessary for an electric circuit to function? Why can't current flow without a voltage?
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48 views

Does the power of the resistor change when the battery is changed?

Wanted to know whether the changing of a battery (potential difference)affects the change of power consumption of a resistor of a bulb. please tell me how the change will occur?
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81 views

Reducing eddy currents, changes the property of the conductor & circuit?

In an attempt of reducing the eddy currents in a conductor, such as having gaps to break the induced eddy currents, would that by any chance change the conductor's orientation from series to parallel? ...
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Why does voltage change in series circuit but not in parallel circuit?

Voltage divides after every resistor in series but not when placed in parallel. Please explain this with using very less or no mathematical equations. I have tried searching for an answer online but ...
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77 views

Which is more important, current or potential difference?

If i have a bulb rated 4V, 4A, and my power source is 2V, 2A. Should I use a step up or step down transformer to make it 4V, 1A or 1V, 4A? Which wold make it glow brighter?
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155 views

How do domestic appliances work at different voltages when the applied voltage is same for every appliance?

Generally, the electric connections at home are in parallel combination. How is it possible for a geyser(220 Volts) and a cellphone charger (5 volts) to operate at different voltages in a parallel ...
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21 views

How does static protection really work?

I've read that while working with circuits you want your body to stay at the same voltage as the components you are trying to protect. So you're supposed to connect those wrist things to one of the ...
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3answers
99 views

What is the voltage at every pair of points along a ideal wire that is connecting the two terminals of a battery?

If you stick a wire across a battery, obviously it is going to discharge the battery. This will be due to a voltage difference between the two terminals. However, the equation $V = IR$ tells you how ...
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Is their a visual difference between air-gap sparks of the same voltage but different current?

For example, if this spark gap has a kilovolt of power behind it @ 1A and the other is also at a kilovolt but is @2A will there be a visual difference (i.e. will the one with higher current be ...
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45 views

Is it possible to raise the voltage of a power source by lowering its current indefinitely (i.e. transformers)?

Let's say you have a D battery. You wire it up to the primary of a step-up transformer, which you then in turn wire up to another step-up transformer,...etc. Is there a limit to how high the voltage ...
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197 views

Is my understanding of electric fields accurate?

Could someone please help me and let me know if the statements below are any accurate? I am struggling trying to understand what electric fields are and I could really use some help! An electric ...
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2answers
482 views

What actually happens at the microscopic level in a Zener diode in reverse bias?

A Zener diode is used as a voltage stabilizer. The graph of current vs voltage of Zener diode clearly shows that there is a constant voltage across Zener after the breakdown voltage as the current ...
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133 views

Electric potential difference

From what I have read, since electrical potential is essentially EPE/unit of charge, it would be position dependent (relative to the electric field). Electrical potential difference is then defined ...
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569 views

Resistance & temperature of semiconductor

From what I have read about semiconductors, the reason their IV characteristic shows a decrease in resistance is because as voltage is increased, current is increased. However, the reason for the ...
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268 views

Ohm's Law Question?

Since $V=IR$, if you were to have say a $5\:\mathrm{V}$ source connected directly to ground, no components in the circuit at all, you would need to add resistance for the current to flow? Or is there ...
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203 views

Is it low current or low voltage that dims a bulb?

At times we have dim bulbs due to some fault from national grid, what I want to know is if this fault is low current or low voltage. Other times electrical appliances blow-up, is that high current or ...
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79 views

Confusion with potential difference [closed]

I was trying to solve a hard problem involving a circuit like this: Find the reading on the voltmeter (red ones are resistors) I don't know how to think about potential difference across branches ...
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57 views

How to apply voltage source in FEM when solve Maxwell equation?

I need to solve the Maxwell equation of electric field by finite element method. In this function, the right hand side is the current density. However, in my problem, the voltage source with 1 MHz ...
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167 views

Filament lamp: Negative part of I/V characteristic?

I don't understand the negative part of the graph. It shows that the resistance is decreasing as the voltage goes from negative towards 0. What does a negative voltage mean and why does the graph ...
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432 views

Voltmeter in series with a component?

I always see voltmeters connected in parallel with a component, but what happens if you connect it in series? I think it's due to the high resistance of a voltmeter but I don't really see why this ...
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142 views

Filament lamp gets hot, metallic conductor doesn't?

Keeping the temperature constant, if you increase the voltage across a filament lamp and a metallic conductor, the filament lamp gets hot but the metallic conductor doesn't. Both are made of metal so ...
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93 views

Efficiency of an electric motor? [closed]

Question: An electric motor runs off a 12V d.v. supply and has an overall efficiency of 75%. Calculate how much electric charge will pass through the motor when it does 90J of work. Can someone tell ...
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83 views

Capacitors and Voltage

Imagine if I have a capacitor, connected to a battery of $12 V$. After charging the capacitor, I increase the plate separation. Then my capacitance decreases, right? But charge should be ...
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78 views

Does sending current upwards reduce the voltage?

I was thinking about relativistic situation of having a vertical wire on a neutron star or high-gravity environment and then say if I send current upwards (away from the ground) will the voltage be ...
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42 views

Current function of voltage, Taylor series

Why can the current as a function of voltage for any device be written as a taylor series? Is it because voltage can be written as V0 Cos wt and then I = V/R ? I'm confused on this.
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75 views

Why is the zero of electric potential taken to be $r = \infty$, rather than $r = 0?$

Wouldn't it make more sense if it was taken to be zero at $r = 0$? This seems to imply that with a negative test charge at $r = 0$ from a positive point charge, $V = -\infty$, which I have trouble ...
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875 views

What determines the forward voltage drop for a diode?

I have always had the idea that the forward voltage drop in a semiconductor diode was related in a simple way to the bandgap energies in the semiconductor. However this is apparently not the case: ...
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706 views

Electrostatic notion of voltage as it applies to circuits

I have a question that's been bothering me about electric fields, voltage, and circuit analysis. Initially, I came to understand voltage as it was taught in the context of electrostatics - through ...
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33 views

Is the induced EMF dependent on the conventional or actual flow of electrons?

I have been studying Faraday's Law and Lenz's Law and the flow of current to oppose change in flux linkage. My question is whether the actual flow of electrons to the top of a material makes the EMF ...
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1answer
88 views

Energy, Voltage Drop, and Current

In an electrical circuit consisting of just a source and some load, when current hits the load, the voltage drops. This means that the potential energy of the charge drops. If the potential energy ...
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2answers
266 views

What is the voltage of an average carpet static shock? Can you make it lethal?

I think I heard somewhere that it was in the thousands of volts, but it had extremely, extremely low amps. Could you somehow transform the current to make it larger or something? Or does the equation ...
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How do I choose the right value of $r$ to find where the electric field is zero?

Sorry for the long question. I'm having a difficult time trying to explain my confusion. I have a positive point charge$\ Q_1 =+q$ at the origin and a negative point charge $\ Q_2 = -2q$ at $\ x=2$ ...