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

learn more… | top users | synonyms

2
votes
2answers
65 views

Can pulsating DC current be transformed?

Since pulsating DC current is changing, why doesn't it induce a changing magnetic flux in the transformer core? Is it able to induce a transformed current in the secondary coil?
1
vote
1answer
36 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. ...
1
vote
3answers
68 views

What is the potential difference between $a$ and $b$ in this basic circuit, when the switch is open? [closed]

My professor says the potential difference between $a$ and $b$ is the difference between the voltages on the top left capacitor and the bottom right capacitor. My friend and I however both think it's ...
0
votes
1answer
43 views

Does the current in a resistor depend on the speed of electrons?

If the speed of electrons in resistor is slow, then will the current be slow and if the speed of electrons is fast, then will the current be fast? Does the current in a resistor depend on the speed of ...
0
votes
1answer
44 views

How do these voltage vs. current graphs demonstrate how the resistance of each conductor changes during the experiment?

The method for the experiment was as follows: Connect the circuit shown above using the globe as a conductor and then replacing the globe with a 10Ω resistor. In each case record the voltmeter and ...
3
votes
1answer
63 views

If current takes the path of least resistance, why do parallel circuits work? [duplicate]

Why doesn't all the current flow down the path with the weaker resistance instead of dividing and going through both resistors (in a parallel setup with 2 unequal resistors)?
0
votes
2answers
67 views

Is resistance the gradient in a $V/I$ graph?

We have a circuit where there is a variable resistor, and we increase this resistance at a steady rate, while increasing current. Thus we have increasing voltage. The gradient is defined by $dy/dx$. ...
2
votes
2answers
56 views

Solving circuit problems

I'd like to know why in a parallel loop, the voltage, along with the current, isn't divided. e.g. in this image from a youtube video the voltage in parallel loop is the same across both ...
0
votes
3answers
95 views

How does an ammeter in a circuit work?

Apologies for this simple question, but I'm having trouble grasping the concept of how an ammeter works. Taking the following circuit as an example: When the switch is closed, current flows ...
0
votes
2answers
80 views

Applying the Symmetry of DC Circuits

While practicing for a notoriously difficult exam I have continued to come across questions like the following and despite my efforts to find resources on them, I can't seem to make sense of it. ...
0
votes
1answer
59 views

Why is it necessary for a circuit to be complete?

Can electrons not flow through a load if they do not have a path to flow to the positive terminal of the battery? Why is it absolutely necessary for electrons to end up at the positive terminal?
2
votes
2answers
82 views

In a circuit one light-second long, does it matter where in the circuit the switch is placed? [duplicate]

I was looking at this textbook example that was posted to reddit: The accompanying comments basically thrashed it saying everything was wrong. I had a specific question about it, though, and this ...
0
votes
1answer
34 views

Would optical signal processing still suffer from slew rate?

In electronics, analog signal processing/computation suffers from parasitic capacitance which leads to slew rate—which is the maximum change of voltage allowed, so handling super-high frequency ...
1
vote
1answer
35 views

Capacitance question

A capacitors capacitance, C is equal to Q/V right? If Q was somehow cut in half, would the potential difference also be cut in half, since V is directly proportional to Q? And if so, Its C would be ...
1
vote
0answers
49 views

Internal resistance of a battery

It is my understanding that internal resistance of the battery is mainly due to resistance of its electrodes and electrolytes. During the charge or discharge of the battery, there's a potential drop ...
0
votes
2answers
78 views

Determine brightness of bulbs in a sImple parallel circuit [closed]

I have a parallel/series circuit given in the following link: The question, listed here: Suppose that you were to unscrew light bulb $L3$. what would happen to the other bulbs? A. $L3$, ...
0
votes
1answer
34 views

Simple two volt source circuit - Current [closed]

THIS CIRCUIT: A=5.6 kΩ , B=5.6 kΩ, and C=10 kΩ. How the HECK do I find the currents through each resistor? Absolutely no clue. Note: I understand Kirchhoff's Laws and Ohm's Law perfectly well - ...
0
votes
2answers
71 views

Where does a straight conducting wire get its capacitance?

If I take a simple piece of conducting wire (of which I can calculate the resistance from the wire dimensions and resistivity of the wire material) and connect it across the terminals of a battery of ...
0
votes
1answer
41 views

Can there be an electric current drawn through a resistor from just one terminal of a battery?

The question will appear a little more sincere from the attached diagram. Will there be any flow of charge at all once the switch S is closed? If yes, then by what mechanism? for how long? What ...
0
votes
1answer
12 views

Phase angle of a circuit

Above is the problem at hand. I know how to calculate the angular frequency and total impedance of the circuit given the information provided. However, I'm not really sure what the question is ...
0
votes
0answers
20 views

Setting up current directions in multiloop circuits with more than one battery

I'm currently working on this problem: I must find the current in each battery. I have certain doubts when estipulating the currents: How many $i$ exists in this problem? The current going in a ...
0
votes
2answers
48 views

Why does a capacitor in an AC circuit allow a lamp to glow continuously

How does the capacitor allow the lamp to glow continuously, but would not do so if the circuit was DC.
1
vote
3answers
42 views

How to detect if resistors are in parallel or series?

Some circuits are easier to see which resistors are in parallel or series. However, when faced with a more complex circuit, I can't figure out which ones are in series or parallel. I am currently ...
4
votes
3answers
694 views

Why do Capacitor Inductor circuits Oscillate instead of reaching equilibrium?

When the capacitor is fully charged there is a potential difference between its poles and that creates a current. This current would create a magnetic field that is changing in the Inductor (because ...
1
vote
0answers
41 views

Coupling of LC circuits

I am reading an old article in a physics journal in which the author explains that the frequency between two identical, but capacitively coupled oscillators becomes ...
2
votes
1answer
64 views

Visualising current in the LCR circuit

I just went through the theory of the serial LCR circuit. There current and voltage are 90 degrees out of phase with each other. Now I was trying to imagine an animation with just dots. And I ...
3
votes
0answers
51 views

Can a magnetic lock be negated or overcome by a stronger electro magnet? [closed]

Magnetic locks seem to be fairly standard on modern buildings. Is it, though, possible to negate a magnetic lock my placing an oppositely-polarized, strong electromagnet across from the magnets on the ...
1
vote
2answers
144 views

Steady-State Current

I am in the process of completing some homework and have come across a question that says: "What is the steady-state current?" It is asking in reference to a circuit that includes two capacitors in ...
1
vote
0answers
26 views

How can the response at the terminal end of an infinite ladder network be solved?

In a recent post: How can the transfer function of an infinite ladder network be used to solve real world problems? I reference how one can solve the transfer function (impedance) of an infinite ...
1
vote
1answer
99 views

How can the transfer function of an infinite ladder network be used to solve real world problems?

In his lectures on Physics, Feynman illustrates a mathematical 'trick' in formulating the impedance of an infinite ladder, LC network. It basically counts on the assumption that adding one more 'rung' ...
0
votes
1answer
21 views

Short Circuit Fires

I understand that if there’s low resistance, Ohm’s law shows that the current drawn will be very high. However, isn’t resistance what causes heat in a wire? I get there’s a lot of current going ...
0
votes
3answers
32 views

Open Circuits vs. Charging a Capacator

When you attach a capacitor to a battery via two wires, charge transfer occurs from one of the plates to the other. However, in an open circuit, there is infinite resistance in the dead-ended wire, ...
0
votes
1answer
21 views

How many electrons pased in electrical circuit

Assume I have electrical circuit that is connected to 5V power supply and current straight is 1A. How to know how many electrons are passed in single point per hour?
0
votes
1answer
38 views

If I lick a 9V battery, why doesn't my tongue noticeably get hotter?

Power dissipated is I^2*R, I don't know the resistance of my tongue so I can't tell how much current goes through my tongue. A resistor I have does get hot and I'm guessing it has a higher resistance ...
1
vote
1answer
45 views

Reference for Kirchhoff's Circuit Laws

Does anyone know the reference where Gustav Kirchhoff published his famous circuit laws?
1
vote
0answers
28 views

If a heater was turned on its' own wire, would heating of the wire cause the resistance to increase, thus the current into the heater to decrease?

I'm thinking not, because; A) It wouldn't make much sense in the real world because you'd need to avoid ever turning a heater towards its own wire, and you'd have to regulate the temperatures of any ...
1
vote
1answer
307 views

Significance of Time constants in LR and RC circuits [closed]

What is the significance of a time constant in a circuit? Is there any use of knowing the time at which the charge in a capacitor is 1-1/e times its total charge? What is special about the capacitor ...
1
vote
1answer
45 views

Thevenin theorem

Hi i got the trouble and i miss the concept about v out in thevenin i have the circuit like this so i used voltage divider for finding the voltage at point 1, but how to finding voltage at Vo , ...
0
votes
0answers
43 views

Current through moving bar on rails with non-constant magnetic field

I am working on the problem pictured below and I cannot figure it out. I have been using the equation d[flux]/dt = -BLv and V = -d[flux]/dt. However, since the magnetic field is not constant through ...
0
votes
1answer
37 views

How soon would electrons start flowing once I closed a switch on a circuit that was one light minute away from the battery

In a circuit, how do electrons "know" when the circuit is closed? To my understanding, they do not start flowing unless the circuit is closed. How soon would they start flowing once I closed a ...
3
votes
2answers
140 views

What happens in circuits where the propagation time of the electric field is significant?

Kirchhoff's current law assumes "that whenever current flows into one end of a conductor it immediately flows out the other end". I want to understand what happens when we cannot make this ...
0
votes
0answers
6 views
1
vote
1answer
62 views

How big of a capacitor would I need to release 5 amps for 0.2 seconds? [closed]

Just what the title says, 5 amps for 0.2 seconds. Please bear in mind that I have absolutely no grasp on electrical wiring, so I would appreciate simple terms. What I need to do is release a burst of ...
1
vote
1answer
42 views

How do i interpret the following electric potential diagrams?

We recently started to learn about electricity in school and I'm trying to understand the concept of voltage(potential differance). From what i understand, electrons flow from the negative terminal to ...
0
votes
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, ...
0
votes
1answer
47 views

Deriving Loop Equations in a Circuit with 2 batteries?

First time posting here, so please help with formatting. I need help deriving loop equations for this becaue the 2 batteries/power supplies are throwing me off. https://i.imgur.com/MJH6mIM.jpg The ...
2
votes
1answer
47 views

Given a large, multiloop circuit with resistors and batteries and I'm not sure how to simplify it. (When NOT to combine resistors?) [closed]

So here's the circuit, and the question is looking for current i: All resistors are 2 ohms and the batteries are 5 volts. I'm trying to apply the resistance combination Kurchov rules to make this ...
0
votes
1answer
40 views

Heat creation of computer electronics

The first thing I learnt in physics was that whenever anything happens heat is created. Irrespective of the process. With that in mind, electronics clearly create heat (ohmic heating I think?). But ...
1
vote
0answers
20 views

energy conservation in an electric circuit

Define a reactive (lossless) and reciprocal two-port by its impedance matrix $[Z]$, so that $[Z]+[\bar Z] = [0]$ and let the source impedance and open circuit source voltage be $Z_s$ and $V_s$ at ...
1
vote
0answers
23 views

Electrostatics effect on resistance values [closed]

Consider two parallel metallic plates separated by a silicon dioxide layer of thickness tox (like a capacitor). In this case I am applying a positive voltage to the top metallic plate. Now due to ...