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

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Voltage and Current in transformers

In transformers, the ratio of the voltages equals the ratio of the turns - so double the output coil's turns and the output voltage doubles. Then, in order to conserve energy, current halves. This ...
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41 views

Is real voltage always the real part of complex voltage?

If I have a complex voltage $V_z$ is real voltage $V$ (i.e. the voltage used in the normal ohms law and the voltage we normally talk about) always given by $V=Re(V_z)$. Does the same apply to current? ...
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69 views

Finding the current in a parallel circuit [closed]

Two resistors are joined as shown. The top resistor receives a current of 3 A. What is the current in the other resistor? What is the current that enters at junction A? I'm confused on how the two ...
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79 views

How is voltage increased from a battery?

I have recently watched a video about a powerful Octa-copter that uses 30,000 Volt brushless motors to propell, the batteries however look quite small about a 19v laptop battery. How is the voltage ...
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93 views

How can there be a voltage when there is no current?

I'm told at school that the Electromotive Force (e.m.f) of a battery equals the potential difference between the terminals of the battery when there is no current. How is that possible? How can there ...
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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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278 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 ...
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136 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)? ...
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1answer
90 views

Why is all the voltage used up in a circuit?

We always assume that all the voltage, in no matter what type of (basic, I guess) circuit we are dealing with, is used up. I can see why this is true. Imagine a circuit with low resistance - and ...
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74 views

Unsatisfactory explanation for the EMF measurement of a battery

Experimentally, I have seen how hooking up a battery to a simple circuit just with a high-resistance voltmeter raises the voltage reading (allegedly to a level equal to the EMF of the battery). ...
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94 views

Why is Lightning referred to as High frequency source?

Lightning strike is categorized as DC because of its electrostatic nature. The negative flash/stroke is found to have 200KA of current with a voltage close to 300KV (cloud to ground). But why is it ...
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99 views

How much voltage should be applied to an object to create a certain amount of charge?

I am curious as to how much voltage should be applied to create a specific charge. Is there a formula to calculate it, and what are the parameters that can affect the relation between voltage and ...
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Are voltages discrete when we zoom in enough?

Voltages are often thought of as continuous physical quantities. I was wondering whether by zooming in a lot, they are discrete. I feel like the answer to the above question is yes as voltages in the ...
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62 views

potential difference in parallel connecting resistors

How could the potential difference be constant across all the resistors of parallel connecting resistors although each resistor has a specific resistance?
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1answer
51 views

Self inductance & time constant formula

Is this a correct formula for calculating the induced EMF of a wire after the current stabilizes/ or while it stabilizes in the beginning of a DC circuit? What is the difference between the above ...
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2answers
49 views

Can current and resistance result in establishing voltage?

I want to know whether current & resistance can cause a voltage across the circuit, according to Ohm's Law $V=IR$. Is it possible to use a low current to produce a high voltage?! How can this be, ...
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1answer
68 views

EMF due to self-inductance? [closed]

I'm trying to calculate the induced $-V$ in a DC circuit when current starts to flow, and reaches it's maximum value. The inductance of the conductor is 1000nH it carries large amounts of current ...
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2answers
68 views

relation between current,voltage and resistance

i want to know the relation between voltage,current & resistance , apart from this ohm's law V=IR.Because in zener diodes,current does not increase accordingly with the voltage.At BREAKDOWN POINT, ...
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1answer
77 views

Interpreting Physics Results Regarding Circuitry Analysis (Highschool Level Physics) [closed]

I conducted an experiment which aimed to detail and record the voltage across series resistors in series circuits. I noticed that: The Final Voltage, V3, stayed the same. The resistors with the ...
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1answer
4k views

Does the phase difference between voltage and current in an LCR circuit exist throughout the circuit?

I know that in an purely inductive circuit the current lags behind voltage by $90^o$, in a purely capacitive circuit vice-versa and in an LCR circuit the current may lag or gain with respect to ...
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1answer
145 views

What maintains constant voltage in a battery?

I know there's lots of questions that address similar situations, (Batteries connected in Parallel, Batteries and fields?, Naive Question About Batteries, and the oft-viewed I don't understand ...
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2answers
518 views

Calculating the electric potential in cylindrical coordinates from constant E-field

I am having so much trouble with this problem. I feel like I shouldn't be, but I am. A uniform electric field, $\vec{E} = E_0\hat{x}$. What is the potential, expressed using cylindrical ...
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5answers
412 views

Ohm's Law Intuition

When we derive Ohm's Law using the Drude Model, we assume at one point of time that $E=V/L$, when is fact, $E=dV/dL$, unless $E$ is constant, in which case the assumption $E=V/L$ is true. But I don't ...
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Questions about voltage

For some reason, I feel like the concept of voltage is escaping my grasp. I've done much research on these forums and through texts, and come across answers that seem quite well thought out, but still ...
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50 views

Is there Phase difference between voltages at end points of a long AC Power line

I found this explanation somewhere: Since wavelength=c/freq so in a AC power line of 50 Hz, wavelength=(3*10^8)/50 = 6000 Km, so voltage phase reverses after 6000 Km in a ac Power line. Now this ...
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Does the photoelectric effect obey Ohm's law?

So, I've been reading about the photoelectric effect for my modern physics class, and I was confused about how Ohm's law works in relation to it. Say we have a photoelectric apparatus that simply ...
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1answer
78 views

Simple Parallel Electric Circuit [closed]

Ammeter (A1) and voltmeter (V) in series have parallel connection to another ammeter (A2). Currents in A1 and A2 are respectively 0.2 and 1.7 amp. Voltmeter's voltage is 6 volts. How should I find ...
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268 views

The Voltage and Current of a Discharged Inductor at the Instant the Switch is Closed

The figure shows an LR circuit with a switch and a 240-volt battery. At the instant the switch is closed the current in the circuit and the potential difference between points a and b, Vab, are ...
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1answer
788 views

How does mass relate to resistance (Ohm's Law)

How can I relate $mg$ to $R$? Just to give you a scenario: If a free hanging weight was tied to a motor... I know the voltage ($V$) and current ($I$) so I can use $V = IR$ to find $R$. What if I ...
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712 views

Is voltage important when creating a magnetic field?

Would a DC circuit that has a high current and low voltage have a powerful magnetic field? I'm trying to create a powerful solenoid. In order to create a powerful magnetic field, I'm focusing more on ...
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18 views

Physics of a conductor gaining potential

Working on electrical engineering but thus far, the physics stack has proven to be a better place to read and ask questions in order to develop a better overall understanding. I am currently waist ...
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1answer
32 views

Form factor and average value [closed]

Why Our Electricity Flowing in the Sequence of 11kv,33,66,132kv,why not Flow in 10 kv,11,12,13,14 that Sequence.
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1answer
118 views

Voltage and potential

I just need a confirmation I've understood this concept and help in a particular problem. So, what I understand under "voltage" is basically a difference between two electrical potentials ...
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92 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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192 views

What is happening to the electrons, and E & H fields, in an antenna with a standing wave inside?

Diagrams like the one shown below are often shown to explain antenna theory, but I have always had problem with the concept of voltage being a wave, and because of this the diagrams never make any ...
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30 views

A voltage-controlled oscillator? [closed]

I already apologize for my medium english... I'm a french guy, not really gifted to recognize electronic circuits : In fact, I need to identify a circuit from is function. So, here is the block ...
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1answer
3k views

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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1answer
760 views

How can rheostat change the current without changing int voltage

NCERT science of 10th, in chapter electricity on page 205, there, a is line written: a component use to regulate the current without changing the voltage ...
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531 views

A confusion in ohms law $V = IR$

ohms law clearly states that potential difference is directly proportional to the current flowing through the wire or V directly proportional to I ______(i) so the formula which is ...
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4answers
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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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271 views

Why isn't there a potential difference across a disconnected diode?

I know this question sounds silly, as if there was a potential difference a current would be created when the terminals are connected together and this would mean energy has come from somewhere. The ...
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257 views

If the current is increased, is there more charge flowing or is it moving quicker?

Problem Current is the amount of charge that is flowing through a component per unit of time. For a given voltage, Ohm's law tells us that if we increase the resistance, then the current must ...
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1answer
315 views

How/Why does voltage reflect?

I'm trying to understand antenna theory again, and I'm again stumped by the concept of VSW (voltage standing waves). I understand standing waves, I remember these from a physics clases, however I do ...
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5answers
15k views

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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1answer
50 views

What is the relationship between the verbal definition and the mathematical definition of some quantities?

I know this is probably an easy question, but it's been a while since I've studied physics and I've started reading some circuit analysis textbooks. I'm finding hard to understand the relationship ...
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415 views

What would the graph between P (power) and i (current) look like if the graph between V (potential difference) and i is parabolic?

The answer is same... That us the graph between P and I will also be a parabola.... Similar to the graph between V and I. But how? Can anyone explain through mathematical approach ? I used ...
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1answer
968 views

What does a positive gradient on a graph of V plotted against I mean in terms of EMF and internal resistance?

According to the equation $V = E-Ir$, the gradient of a graph of $V$ against $I$ should be $-r$ (internal resistance) and the Y intercept should be the EMF. Am I right? In an experiment I used a ...
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343 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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Calculating the Potential from the E-Field

I find that often times I'll be tripped up by questioning whether or not I can do something mathematically, and be unable to come up with a satisfying answer. This is, unfortunately, one of those ...
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1answer
151 views

Current vs Voltage Drive for Loudspeakers [closed]

Please see this article: here I don't know enough EMFT to comment on this but I am working on other tasks for a wireless speaker system prototype called "Busker's Friend". Completing my Schaum's ...