An electronic system, with closed loop current flow, and relative electrical potentials present across electrical components.

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How can current remain same when potential difference decreases?

According to Ohm's law, $$\text{potential difference} = \text{resistance}\times\text{current}$$ Also, current remains the same everywhere. Now when current passes through a bulb, the electric ...
0
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4answers
29 views

Is impedance the ratio of voltage to current at any instant?

My book defines impedance as the ratio between the amplitude of voltage to that of the current (Vmax to Imax), I just wanted to make sure whether its also true for the instantaneous values of voltage ...
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1answer
27 views

Things that must be considered when mass producing a capacitor [closed]

The question is to list four things that must be considered when a capacitor is chosen for inclusion in a circuit which is to be mass produced. Are there a specific set of four things? I've come up ...
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1answer
34 views

To determine the path of current in a complex circuit. (CAP contest question) [closed]

How to determine the path of current in this diagram ? Intuitively, I guess the current won't pass through wire DC... Any help will be appreciated!!!
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3answers
112 views

Power dissipation in AC RC circuit [closed]

Can anyone help me with this question? A 20 A peak-to-peak 60 Hz current passes through a 0.01 µF capacitor which is in series with a 33 Ω resistor. What is the power dissipation? I have ...
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3answers
94 views

Why electrons flow through a wire connected to a battery?

I would like to know why does electrons flow through a wire connected to a battery as said in AC/DC: What's the Difference?.It tells that "the electrons that are stripped from the carbon electrode is ...
0
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2answers
19 views

Opposing currents in a Ciruit

If I have two currents flowing in opposite directions in a wire where both currents are equal magnitude and their is a bulb on the same wire does the bulb light up at all or is it bright/dim ?
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1answer
23 views

Ohm's law deviation

In terms of superconductivities and diodes (I do not know amything else except these), Ohm's law deviate from a linear relation. I search many titles or tags for this but I did not understand properly ...
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1answer
36 views

Why does this circuit work and the other doesn't? [closed]

if we connect the set up like this the bulb glows but if we connect the [right wire] to the [earth of the left] then the bulb [doesn't glow]. Why does that happen?
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3answers
38 views

Why does adding more components in parallel increase the current?

Why does adding more components in parallel increase the current? Shouldn't the charges be more distributed, so they can't 'push' each other at the same rate anymore?
2
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2answers
39 views

Movement of charges in presence of electric potential difference

This might appear to be a bad question to some but i can't figure out the answer. While reading about an electric circuit, i found this on the web: Over the course of time, one could think of ...
0
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1answer
45 views

what is the analog of electronics for quarks or protons?

Is there an equivalent field for quarks or for protons as there is electronics for electrons where you can build engineer and mess around with things? May be even hack ?
0
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1answer
40 views

Potential Dividers - Why do I need the second resistor?

So I am doing the OCR Physics GCSE course, and I have just learnt about potential dividers in electronic circuits. I get that the first resistor steps down the voltage so a component with a lower ...
0
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0answers
20 views

question about solution [duplicate]

I think it is not dublicate question. Although there are many solution, I did not understand logical mean properly. my question is that in the below circuit, How can I find equivalent resistance? ...
1
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0answers
9 views

explanation of the solution of equivalent resistance [duplicate]

I think it is not duplicate I wonder that explanation of the solution I searched and I found answer to my question.Although there are many solution, I did not understand logical mean properly. my ...
1
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0answers
12 views

solution of the equivalent resitance [duplicate]

I searched and I found answer to my question.Although there are many solution, I did not understand logical mean properly. my question is that in the below circuit, How can I find equivalent ...
0
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3answers
52 views

Potential Difference Across Components in Parallel & Series Circuits

So I have two questions, but they're kind of linked so I'm putting them in one. 1) I have a simple circuit with a battery connected to three lamps in series. If I then add a second battery but ...
0
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2answers
35 views

What actually goes on in RLC circuit?

I already have difficulty understanding how each of the RLC circuit elements work individually as it is, and I have no idea how they work simultaneously in an RLC circuit. My schoolbook represents the ...
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2answers
34 views

Why don't capacitor charging graphs look like other exponential growth graphs?

Sorry if this question is stupid, but I can't find any answers for this online. Physics websites show that capacitors charge and discharge exponentially. The discharging graphs of charge against time ...
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1answer
19 views

Voltage in a circuit across a metal wire

I have a cell of e.m.f. 2.0V and negligible internal resistance, which is connected to a variable resistor R and a metal wire. The resistance of the metal wire is 3.4 Ohms. The resistance of the ...
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2answers
48 views

Explaining why there is current in a circuit with a capacitor whilst the capacitor is charging

The question I'm trying to answer is part b) of the question below: My answer was: As some of the electrons will initially be repelled by the electric field of the negative plate, there will be ...
0
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1answer
34 views

Capacitors in an AC circuit

Can I combine capacitors in the same way for an AC circuit as I can for a DC circuit (In series or in parallel)? Does the same apply for simplifying resistors?
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0answers
43 views

Can current be induced in a grounded conductor?

I'm engaged in a rather lively debate with a group whose physics I believe to be a bit shaky. Basically they're claiming that if a conductive object is grounded to earth, the current cannot be ...
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2answers
63 views

RC circuit energy [closed]

I am quite new at circuit analysis and I have a question about a RC circuit, with the resistor and the capacitor connected in series. I want to find the energy supplied by the ideal voltage source ...
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1answer
42 views

In the Nernst equation $E=E_{cell}-\left(\frac{0.0592V}{n}\right)\log Q$, what does the $E_{cell}$ represent?

In the Nernst equation $$E=E_{Cell}-\left(\frac{0.0592V}{n}\right)\log Q$$ what does the $E_{cell}$ represent? I read that $E_{cell}$ is the standard state condition of the cell, let us say that we ...
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1answer
31 views

How does a capacitor pass the flow?

Capacitor has just two conductor surfaces which have no touch. How can it pass the electric flow when there's no touch between the surfaces?
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0answers
17 views

Ion Source Design

I want to design a DC arc discharge ion source but I can't find a good book that explains how to do it. Can anyone please recommend me a book or paper that explains this? thanks
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0answers
56 views

How does the introduction of a new ground affect a circuit?

I was talking today at lunch with a friend about getting shocked by a light socket while changing a light bulb the other day. The glass got separated from the metal threads where the positive and ...
2
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2answers
21 views

Inductor circuit

Consider a inductor circuit with an inductor connected to a DC battery and a switch. Initially the switch is open. At time $t=0$ the switch is closed. What will happen to the inductor just after ...
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1answer
30 views

Deriving the charge as a function of time in a discharging capacitor

There is obviously something I have not understood well. In Kirchoff's second law, we take the potential difference of batteries and capacitors with the sign that we traverse it. So, let's assume that ...
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1answer
47 views

Thevenin's Theorem problem

I don't understand why $(c)$ is same with a circuit when removing power source at $(b)$. Isn't this same with this one? But how could this circuit could be $(c)$? . .
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0answers
22 views

Impedance of transformers

What does mean by impedance reflecting? Why this phenomena occur? What does mean by Zl=zs to gain max power but power is constant in transformers?
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2answers
26 views

DC motor, bulbs

What happens when you are getting low voltages ? Why fan becomes slow and bulb become dim ? Dye to low voltage or current? If power is V*I then due to low voltage current becomes low or not Many ...
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0answers
34 views

Finding Equivalent Resistance [closed]

Consider a square $ABCD$ with $O$ as the point of intersection of diagonals. Every side has a resistance of $R$ ohm across it. $AO,BO,CO,DO$ also have a resistance of $R$ ohm across them. What is the ...
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0answers
37 views

Finding Voltage across a resistor in a circuit using mesh current analysis [closed]

I'm trying to find $V_{th}$ by mesh current equation. Mesh A: +12V +$i_a \cdot 6Ω =0 ???$ There's a current source shared by mesh A and B. Current $i_b$ is in the same direction as current ...
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1answer
34 views

Equivalence between voltage drop across capacitors and resistors?

In simulating a circuit, comprised of 2 capacitors of same size but different dielectrics, their capacitance ratio ${C1}/{C2} = \epsilon2/\epsilon1$. Problem is, in finite element programs, I am ...
3
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1answer
103 views

Do light dimmers save energy and lower your electric bill? [closed]

Or do they just capture the incoming energy and turn it into heat at the unit and save you nothing?
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1answer
46 views

AC Electricity as a Simple Harmonic Oscillator

Can the net motion of electrons in an AC circuit be considered an example of simple harmonic oscillation. Furthermore, how can the general formulae of SHM be adapted to suit a scenario of an AC ...
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1answer
57 views

Validity of Kirchhoff's current law

Is Kirchhoff's current law valid for rapidly varying currents such as a one with a frequency in the order of 10KHz?
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21 views

Triphasor Problem

Given the data presented in the following link I have to get $R$ for $P = 90~\textrm{kW}$ and the line currents $i_1$, $i_2$ and $i_3$. Any ideas?
1
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1answer
37 views

If a purely inductive circuit is started in presence of gravity, will the power source ever run out? [closed]

I have read that purely inductive circuits do no work. So if an Inductor with an AC source, coming from an inverter is set up, will the source of power ever run out due to work against gravity? This ...
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0answers
44 views

Voltage and reactive power

Why are reactive power and voltage related? When the control system of a generator increases/decreases the current of the rotor, voltage and reactive power are increased/decreased.What is the relation ...
0
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2answers
54 views

How does current split in a parallel circuit? [closed]

I'm having trouble understanding why the current that goes through the 6 ohm resistor is 1A when the proportion of the parallel resistors is 2:1 from top to bottom. Could anyone explain how current ...
0
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3answers
43 views

Why fuse needs to be slightly more able to bear current than the appliance?

if I have a bulb with rated current of 4amps then why I need to connect an 5amps fuse?( which has slightly more ability to bear current.)
1
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1answer
42 views

Equivalent DC circuit with charged conductors

I am trying to find equivalent circuit for a circuit composed of interconnected capacitors when isolated pieces of conductor may carry nonzero electric charge, and I have been struggling with this ...
0
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1answer
36 views

power in an ac circuit - difference between in series and parallel

In AC-circuits, we have different kinds of power: active power $P$, reactive power $Q$ and apparent power $|S|$. Let's say we have a circuit with a resistor $R$ and an inductor $L$. My understanding ...
0
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1answer
54 views

How to find when an LRC circuit is critically damped mathematically, given a set of voltage/time data?

In an undergraduate-level experiment to approximate the resistance at which an LRC circuit system is critically damped, I found the resistance range within which the system is likely to be critically ...
1
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3answers
68 views

What is reactive power?

I am trying to understand what is reactive power. I have read that it has a relation with voltage, that is has a relation with the creation of a magnetic field in a motor, that it is coming and going ...
1
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0answers
28 views

How Calculate the electric field into capacitor [closed]

Hello i have a problem with this exercise with capacitor, I have to calculate the electric field between the capacitor plates (neglecting the edge effects ), but I do not know how to do Text: A plate ...
1
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1answer
17 views

Does electron drift model apply to current in liquids

The electrons in a metallic conductor, tend to drift at abysmally slow speeds, but still a current is able to flow through it, because the net movement is in the direction of the applied emf. How is ...