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

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If I charge a battery using a much higher current, can it explode?

If I have a 12V 4Ah lead acid battery and use a battery charger that, let's say for example, can charge 10A, 50A, or 100A. If I theoretically turned it to 100A will the battery explode? I understand ...
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22 views

Understanding parallel plate capacitors

I need help with understanding this assignment. I originally though of using the equation of Eo*A/D = Q/ΔV but I don't know how to answer this without actual numbers to plug in besides the epsilon-not ...
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1answer
34 views

What happens to the resistance, voltage and current when DC passes through saltwater?

I have a circuit of a battery(1.5V or 9V) connected to a multimeter, a connected to 2 metal pieces in water(distilled)(see picture, in place of the LED is a multimeter). With the addition of salt 1. ...
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1answer
242 views

Which power equation to use: $P = I^2 * R$ or $P = V^2 / R$?

Given are ideal max voltage $V = 200\;\mathrm{V}$ and max current $I = 5\;\mathrm{A}$. Therefore: ideal resistance is $$R = \frac VI = \frac{200 \;\mathrm{V}}{5\;\mathrm{A}} = 40 ...
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1answer
112 views

Spherical magnet inside a solenoid

When passing a bar magnet through a long solenoid why is it that the induced emf when the magnet is in the middle of the solenoid is zero? And if a spherical magnet is put inside the solenoid, will ...
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1answer
59 views

Variation of Peak Current and Peak Voltage with Capacitance in an AC circuit

The relation of Peak current, Peak voltage and Capacitive Reactance in Alternating Current is given by: $$i_m=\frac{v_m}{X_c}$$ and $$X_c=\frac{1}{C\omega }$$ So if we have a circuit with a ...
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1answer
33 views

Why is current shared in a parallel circuit but not a series circuit?

Electricity test coming up. It's not clear to me why current is shared in a parallel circuit but not a series circuit.
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36 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 ...
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1answer
30 views

Induced EMF dependent on terminal wire connection?

Figure(a): When a conductor moving inside magnetic field, of a given length at a certain velocity the induced EMF is: $$\epsilon = vBL$$ However, what if we changed the position where the bottom ...
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1answer
52 views

What is voltage in a circuit?

What is voltage in a circuit? We just started learning about electricity in my school. From what I understand; potential is potential energy per Coulomb and voltage means difference in potential. So, ...
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1answer
34 views

How can I redraw this circuit where I can apply Kirchoff's Voltage and Current Law to get correct Voltage at V?

I thought I can draw the -5V as a source but it did not turn out to be right, unfortunately.
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1answer
51 views

Voltage Circuit

I feel that I don't understand how voltage works in a circuit. I understand voltage to be electric potential energy per unit charge (kq/r). In the case of a circuit, electrons flow from low potential ...
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1answer
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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1answer
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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1answer
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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128 views

Current and Resistance-Effects of the Length of the Wire

Two wires of the same material are both connected to a 9-V ideal battery. They have the same cross section area but wire 2 is twice longer than wire 1. Compare the following quantities by answering ...
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1answer
60 views

Different voltages between same point?

In this circuit, we determine that the emf needs to be reversed and that its value is 108.75 V. My confusion is that I thought the voltage between any two points must be the same irrespective of the ...
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1answer
182 views

Measured voltage on coil

I have a simple circuit of coil with inductance L $$u_c(t)= -L\frac{di}{dt}$$ and AC source with output voltage $u_s$ What is actually measured by the voltmeter ($u_c$, $u_s$ or $u_s - u_c$)? If ...
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498 views

What is the voltage difference between the Moon and the Earth?

The Moon and Earth are approximately spherical conductive balls and the Earth has a self-capacitance of around 710uF. Is there ever a significant potential difference in the Earth-Moon system? Is ...
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0answers
59 views

Why does electrolysis require a base electrolyte instead of an acid electrolyte?

I am in the process of using electrolysis to remove rust from some old tools. This is the process where you submerge the rusted item in a bath along with a sacrificial piece of metal. You connect a ...
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0answers
117 views

How much current would be generated by polarity reversal of Earth's magnetic field?

Continuing from my previous question Is reversal of magnetic polarity in a planet an instantaneous occurence? A change in magnetic flux is expected to generate an EMF. In the case where the ...
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29 views

When a coil makes a complete turn, why is does magnetic flux double with respect to time?

EMF, $\mathcal{E}$, is equal to -d($\phi$)/dt Where $\phi$ is magnetic flux. Why is it that if from $t_1$ to $t_2$ the coil makes a complete turn and during this turn the normal vector's angle with ...
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13 views

Could a Kelvin Probe Force Microscope, in principal, be used as a voltmeter?

This question goes into the very nature of the work function that the Kelvin Probe Force Microscope (KPFM) measures. https://en.wikipedia.org/wiki/Kelvin_probe_force_microscope Let's say, you have a ...
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22 views

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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140 views

Voltage in a lossless transmission line

I have a question where I'm deriving expressions for different variables within a lossless transmission line. Here's the question as posed: Consider a lossless transmission line of characteristic ...
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19 views

Voltage wave reflections in transmission line loaded by matched resistor

Suppose I have a power source, a transmission line and a resistive load all connected together and all sharing the same impedance. If I send a voltage pulse starting at the power source, traveling ...
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20 views

Potential difference across a resistor

I would like to know if the potential difference between the two ends of the resistance is same as the potential difference between any tow points in the resistance whose length is smaller than the ...
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11 views

How polarized object's polarized atoms behaves like charge?

Electrical polarization is just the shifting of the constituent atoms' protons and electrons in opposite directions. This creates a bound charge, and this bound charge creates voltage and thus an ...
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22 views

Modeling the working of a transformer by pushing magnet into a coil

Let me go step-by-step. First I will outline a simple transformer. There are two circuits next to each other (not touching). One is an electromagnet set-up (with AC supply) and the other has a ...
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37 views

What were the experiments performed that lead to ohm's Law

How was the relationship of $V=IR$ first developed? What were the experiments that were preformed that lead to Ohm's Law? I understand that they had devices during George Ohm's time to measure current ...
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22 views

Fréedericksz transition question

What is the lowest voltage needed for a Fréedericksz transition to occur?
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22 views

High voltage arc stability reasons (in some cases shape of the arc is rapidly changing)

When turning off 500kV switch we can see an arc like on this picture this arc is very unstable, curved, distorted. It consists of many little loops. While on this picture electric arc patiently goes ...
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44 views

Physical intuition behind the fact that current in an inductor lags behind the emf/voltage by $\frac{\pi}{2}$ in an AC circuit

What exactly is the reason that current through an inductor in an AC circuit acquires maximum value after quarter a time period ($\frac{T}{4}$) of the emf getting the max value?
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67 views

Do I Understand Voltage?

Below is a formula involving voltage and potential energy. $$\Delta U = q \Delta V$$ I would like to know if I understand it: If $\Delta V$ is positive, then the charge $q$ has moved from a lower ...
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49 views

How to measure the static electricity voltage?

Some of the Wimshurst machine producers claim their machines produce about 70 000 volts. I wonder how to measure this value. How is it possible to measure the static electricity voltage?
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41 views

I need some clarification about my understanding of voltages and resistance

So I was reading through this question, and I think resolved my query about what voltage actually is. I don't understand what we really mean by voltage drop But I just want further clarification ...
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28 views

Change in magnetic field region reduces overall voltage due to change in resistance?

Consider the following diagrams: Diagram(1): A large conductive slab($C$) with resistance ($R$) and region with magnetic field($B$), the conductor moves to the right as indicated with ($v$). ...
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21 views

Voltmeter across two loops

If one terminal of a voltmeter is connected to a closed loop with current and the other to an open loop, will there be a reading? Theoretically, there is a potential difference across the terminals, ...
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51 views

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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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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132 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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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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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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79 views

Induced-EMF in a parallel circuit, vs a series circuit?

I wanted to know the difference between the induced-EMF in a series circuit layout, vs a parallel circuit layout. In a series the current would stay the same,however, the induced-EMF would increase? ...
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72 views

The affect of high frequency and high voltage AC on induction

I am designing an induction system to wirelessly transfer power a short distance. I was planning on using resonant inductive coupling to increase the efficiency. The Inductance of my coil is about ...
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0answers
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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90 views

Potential difference and voltage

Is potential difference between two points the voltage? (or) Is voltage the potential difference between two points? (or) Are they both the same?
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50 views

Li-ion Battery charging

Why are constant current mode and constant voltage mode needed when charging Li-ion batteries? Why do we apply saturation charge even after the cell voltage reaches 4.2V? What exactly is 'I-sense' in ...
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105 views

How to achieve Gigavolts?

I was searching the internet when I found this article http://arxiv.org/abs/0804.1764, about achieving high voltage and power to ignite thermonuclear reaction by inertial confinement, the plan was to ...
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145 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 ...