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

learn more… | top users | synonyms

-1
votes
1answer
42 views

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
votes
1answer
44 views

Adding two same DC voltage source in parallel

In a parallel circuit(imagine two branches),with one DC voltage in a branch and another DC voltage in a branch, what is the method of computing the total DC voltage? The voltage through each component ...
0
votes
1answer
43 views

What is the current passing through wire AB as a function of angle theta? [closed]

This is a high school contest(CAP) question: Consider a circuit made of a wire with uniform resistance in a shape of a circle as shown in the picture. The circle is connected diagonally from point A ...
0
votes
1answer
18 views

Reducing voltage with resisitors [closed]

I am working on a project in structure, in which i have to rotate the second storey of my building, now my assembly consists of 12 v battery connected in parallel with 12v motor which is connected to ...
-1
votes
1answer
43 views

Why is it said that electric current always flow from higher potential to lower potential?

Why is it said that electric current always flow from higher potential to lower potential? It is said that current flows from positive terminal to negative terminal, but it is actually the negative ...
1
vote
1answer
21 views

How does electricity travel through a set of resistors arranged parallel to each other? [duplicate]

For calculating net resistance in a combination of parallel resistors we use 1/R=1/r1+1/r2+1/r3....but electricity must travel through least resistance. Then how does this relation come in use? I am ...
1
vote
0answers
35 views

Logarithm of the voltage of the inductor in RL circuit experiment is nonlinear with time

I performed an experiment about the RL circuit, with following circuit: (I used the PASCO RLC circuit lab.) By Kirchhoff's voltage law, (denoting the emf of the signal generator $\mathscr E$, ...
0
votes
0answers
21 views

Resistance of a plate of smaller plates made up of different materials?

This problem propped in my head yesterday related to a project I'm working on and I just can't figure out how to crack it! If we have a large plate made up of nxn smaller plates, what is the ...
3
votes
5answers
58k views

Why the bulb glows brighter?

If the total current is divided into the branches in a parallel configuration and it is constant in series. How come the bulbs glow brighter when connected in parallel than when connected in series?
-1
votes
3answers
128 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 ...
0
votes
4answers
32 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 ...
-1
votes
1answer
35 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!!!
-1
votes
1answer
60 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 ...
2
votes
4answers
163 views

Why current loses its energy?

Can someone explain or give a link to explanation why current looses its energy? For example in simple circuit with lamp. I understand that the energy is spent for heating and lighting. But how ...
2
votes
4answers
460 views

Path of EM wave propagation in a circuit wire

The image is my visualization of drift velocity and electromagnetic (EM) propagation of charge wave in a closed circuit. The slow drift velocity of the electrons follows the path of the circuit (a ...
2
votes
3answers
458 views

If we connect a block of p-type semiconductor only to a positive terminal, will it become positively charged?

Connect the positive terminal of a battery to a piece of p-doped semiconductor, say, silicon doped with boron. Will the terminal pull electrons out of the doped silicon, or equivalently, inject holes ...
1
vote
3answers
203 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
votes
2answers
23 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 ?
3
votes
3answers
10k views

Why is equivalent resistance in parallel circuit always less than each individual resistor?

There are $n$ resistors connected in a parallel combination given below. $$\frac{1}{R_{ev}}=\frac{1}{R_{1}}+\frac{1}{R_{2}}+\frac{1}{R_{3}}+\frac{1}{R_{4}}+\frac{1}{R_{5}}.......\frac{1}{R_{n}}$$ ...
0
votes
1answer
48 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 ?
-1
votes
1answer
38 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?
2
votes
2answers
45 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 ...
1
vote
3answers
71 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
votes
2answers
147 views

Ambiguity on the notion of potential in electrical circuits?

As everybody else I have been taught elementary electrical circuits from secondary school to engineering level in analog electronics at university. Invariably, the notion of potential used to ...
0
votes
1answer
53 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 ...
1
vote
0answers
13 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
votes
0answers
23 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
vote
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 ...
0
votes
3answers
75 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
votes
2answers
42 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 ...
0
votes
3answers
208 views

In which direction should flow of electric current be taken while solving problems?

Consider a simple circuit with a battery of $\theta\ \text V$s, and two resistors of $R_1 \ \Omega$s and $R_2\ \Omega$s connected in series. Let us assume that $R_1$ is connected nearer to the ...
0
votes
1answer
24 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 ...
0
votes
0answers
18 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
0
votes
2answers
60 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 ...
1
vote
3answers
710 views

Why is there electric field OUTSIDE a battery?

Correct me if I'm wrong, but a battery's electric field is like an electric field of a capacitor consisting of two parallel plates. But we know that the electric field outside the two plates is zero. ...
-3
votes
1answer
49 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 $(c)$? . .
0
votes
1answer
35 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?
0
votes
2answers
93 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 ...
-1
votes
1answer
53 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 ...
0
votes
0answers
45 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 ...
1
vote
1answer
34 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?
5
votes
1answer
122 views

Analogy in combination of batteries in series and pn junction diode circuit to find potential difference

Can I use the analogy of combination of two batteries to get the potential difference between two points(by applying Kirchhoff's law) in case ,if a pn junction diode is used in the place of other ...
2
votes
3answers
6k views

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 ...
0
votes
0answers
59 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
votes
2answers
24 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 the ...
1
vote
1answer
35 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 ...
1
vote
2answers
31 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 ...
0
votes
0answers
23 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?
1
vote
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 ...
1
vote
1answer
633 views

How to imagine the first few moments of an LR circuit?

For example, there's a very simple circuit which only contains on resistor. So according to Ohm's law, we have: $\mathrm{emf} = IR$ As we know when time $t = 0$, the current must be $I = 0$. However, ...