# What is Parallel circuit: Definition and 109 Discussions

Two-terminal components and electrical networks can be connected in series or parallel. The resulting electrical network will have two terminals, and itself can participate in a series or parallel topology. Whether a two-terminal "object" is an electrical component (e.g. a resistor) or an electrical network (e.g. resistors in series) is a matter of perspective. This article will use "component" to refer to a two-terminal "object" that participate in the series/parallel networks.
Components connected in series are connected along a single "electrical path", and each component has the same current through it, equal to the current through the network. The voltage across the network is equal to the sum of the voltages across each component. Components connected in parallel are connected along multiple paths, and each component has the same voltage across it, equal to the voltage across the network. The current through the network is equal to the sum of the currents through each component.
The two preceding statements are equivalent, except for exchanging the role of voltage and current.
A circuit composed solely of components connected in series is known as a series circuit; likewise, one connected completely in parallel is known as a parallel circuit. Many circuits can be analyzed as combination of series and parallel circuits, along with other configurations.
In a series circuit, the current that flows through each of the components is the same, and the voltage across the circuit is the sum of the individual voltage drops across each component. In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents flowing through each component.Consider a very simple circuit consisting of four light bulbs and a 12-volt automotive battery. If a wire joins the battery to one bulb, to the next bulb, to the next bulb, to the next bulb, then back to the battery in one continuous loop, the bulbs are said to be in series. If each bulb is wired to the battery in a separate loop, the bulbs are said to be in parallel. If the four light bulbs are connected in series, the same current flows through all of them and the voltage drop is 3-volts across each bulb, which may not be sufficient to make them glow. If the light bulbs are connected in parallel, the currents through the light bulbs combine to form the current in the battery, while the voltage drop is 12-volts across each bulb and they all glow.
In a series circuit, every device must function for the circuit to be complete. If one bulb burns out in a series circuit, the entire circuit is broken. In parallel circuits, each light bulb has its own circuit, so all but one light could be burned out, and the last one will still function.

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1. ### R and C parallel circuit

If i have the R and C circuit in parallel, the battery voltage is completely applied to the capacitor of 10uF since it is in parallel, but as per the capacitor behavior it shall charge slowly. So which is correct? I mean is it wrong connection?
2. ### Why Capacitors in Parallels vs. Series: Coaxial Capacitor Case

So my idea was to separate the capacitor into two individual ones, one of length ##l - a## filled with a vacuum and one of length ##a## filled with the glass tube. The capacitances then are $$C_0 = \frac{2 \pi \varepsilon_0 (l-a)}{\displaystyle \ln\left( \frac{r_2}{r_1} \right)}$$ for the...
3. ### Engineering Solve Superposition Theorem for R1, R2 Circuit

i have this question and i just want to make sure i am on the right track as i know there are quite a few steps to this to get to the final soultions i need to find Current at r1 voltage at r1 current at r2 voltage at r2 i have so far split this into 2 drawings so i am dealing with one power...
4. ### What is the voltage in a parallel circuit?

Potentials in points E, F, A, B are equal because there is no resistance. In my opinion, losses of potential energy in the resitors R1 and R2 are not equal (potential C ≠ potential G). Then why do we say that voltage in this circuit is the same?
5. ### Engineering Simplifying a series / parallel circuit and calculating unknown values

Given the circuit above, I have to solve for the labelled currents, find V total and R total accordingly. 1A is flowing through the 5Ω resistor as shown. Assuming electron flow (negative terminal to positive) for circuit. The connector in the middle was somewhat confusing. Without it, this...
6. ### RLC Parallel Circuit: Analyzing Current & Voltage at t=0-

These are my attempts at doing this question, and I was wondering if I am correct so far. At t= 0-, i(L) will be 0A, since the capacitor acts as a open circuit. However, I'm not sure why V(c) at t=0- will be -20V as given by the answers. Won't it be 0V? Moving on, since current in inductor and...
7. ### R_th wrong while applying series and parallel simple theory

Summary:: Trying to find Rth but I do not get the same value as the one from the solution. [moderator: moved from a technical forum. No template.] I am trying to find Rth to solve this problem, however once I simplified it, I get a value of 700.745 Ω while in the solution, the answer is...
8. ### How does the current divide in parallel inductors?

I apologize using English fluently because I am not an Enlgish speaker. When I tried to solve this problem, I used current divider rule. So, $$i_o(t) = \frac{3}{3+5}*4e^{-2t} = 1.5*e^{-2t} A$$ However, This was wrong. The answer is $$1.5*e^{-2t} + 0.5 A$$ If I use $$V_O = L*\frac{di}{dt}$$...
9. ### Parallel circuit with internal resistance

4 resistors R1= 10 Ohm R2= 7 Ohm R3= 6 Ohm R4 = 18 Ohm, internal resistance of source is 0,5 Ohm and supply voltage is 27V Total resistance in parallel resistors 1/R = 0.465 taking the inverse of that i get 2,15 Ohm. Add to that the internal 0,5 and the total comes out to 2,65 Ohm. Total...
10. ### Current through source in AC circuit with R & LC in parallel

Homework Statement In the circuit diagram shown , Xc = 100 ohm , XL = 200 ohm , R = 100 ohm , the effective current through the source is ? Homework Equations Z= √( R^2 + ( XL - Xc)^2) Vrms = Irms/ ZThe Attempt at a Solution I tried to draw the phaser diagram and calculate the relation...
11. ### Why does current choose the short circuit path?

I've seen answers saying that electricity takes path of least resistance, I know this and there is no need to explain this for me. A forum's answer told me that the electrons initially flow through to the path with resistance and eventually becomes congested (redirecting the remaining electrons...
12. ### Potential Divider Circuit

Homework Statement Homework EquationsThe Attempt at a Solution When we will move the contact X towards P, the potential difference should be maximum across the potential divider. I work out A as my answer but I think it is wrong.
13. ### Parallel and Series Circuit

Homework Statement I'm asked to find a combination of resistors (parallel and/or series) that uses resistors of 25 Ω, 100 Ω, 50 Ω, and 50 Ω. They should add up to give a total resistance of 62.5 Ω. Homework Equations Req for parallel = 1/R1 + 1/R2 + ... Req for series = R1 + R2 + ... The...
14. ### Engineering Electrical circuits: when all switches are closed, what is R?

Homework Statement https://pasteboard.co/Hj3g5Km.jpg When both switches 1 and 2 are closed,what is the total resistance of the set up? I couldn't figure out which resistors are connected in parallel and which resistors are actually in series in this set up when both swtiches are closed. I...
15. ### Current Dividing in an Electrical Circuit

A circuit contains a 7.5V d.c power supply and three resistors. The total resistance of the circuit is 30 ohms. Why will the largest current in the 18 ohm resistor? As far as I know is that the smallest current will be in 60 ohm resistor because it has the maximum resistance. Please explain...
16. ### What's the total resistance in this circuit?

Homework Statement https://imgur.com/3H3pCkD R is the resistance of each resistor, determine total resistance in the circuit. (see the image in the link above) Homework Equations R=1/R₁+1/R₂+1/R₃+... (in parralel circuit) R=R₁+R₂+R₃... (in series circuit)The Attempt at a Solution I'm...
17. ### Two like capacitors in parallel

I'm having a little trouble understanding capacitors in parallel and series. I understand that if there are two capacitors in a circuit with a potential difference Vab then the potential difference across the capacitors is also Vab. Every example I have seen have been for two capacitors with...
18. ### Can you help me find the current through the 15 Ohm resistor branch?

Homework Statement Homework Equations I = VR Series = current the same, voltage different Parallel = current different, voltage the sameThe Attempt at a Solution Is the 1 ohm and 15 ohm parallel? I'm still learning to differentiate it. If yes, then R = 15/16 ohm Is the R series to 5ohm? If...
19. ### Engineering Parallel Circuits: Learn How to Connect 2k & 4k

Homework Statement Homework Equations Parallel circuit The Attempt at a Solution How can we see 2k//4k (parallel)? There are 2*2k & 2*4k. thanks. (Though I can obtain the same answer by KVL)
20. D

### What happens in a parallel circuit when more resistances are added to it? And why?

Hello. Something has been bothering me for a while now: Consider a circuit with one battery and only one light bulb, for example. We have a value for the resistance of the bulb (R) and there is also one value for voltage (U) and one for current (I). Now, let's imagine that we connect a new...
21. ### Solving the Parallel Circuit: R=25, X[c]=100, X[L]=25

Homework Statement what is the value combined impedance of the parallel circuit ?when R=25 ,X[c]=100 and X[L]=25 Homework Equations I think we use this equation to solve parallel impedance .... The Attempt at a Solution...
22. ### Parallel circuit of current sources

Assume I have a parallel circuit of current sources with 5 current sources generating 1mA each. Therefore from both the terminals I will get 5mA total. Now if I add a battery to one of the terminals where current(i) will flow into my circuit. If i = 50mA, will I get 55mA current from another...
23. ### Why would a parallel circuit (or in blood) decrease resistance

Hi PhysicsForums, Why would a parallel circuit(or in blood) decrease resistance? Here is my thought experiment and where I got stuck: Say from aorta to one arteriole, the resistance is super high on that flow(this big amount of flow is entering a tinier area), but add more arterioles and we...
24. ### AC Parallel Circuit: Current In-Phase with Voltage?

Current is in phase with voltage in series. What about in parallel?
25. ### Thevenin reduction of network for fault analysis trouble.

Homework Statement Reduction from top network to bottom network in the screen shot. I can not find the steps that have been taken to do this. Fault impedance = Zfa = Zfb = Zfc = j0.5 Homework EquationsThe Attempt at a Solution in hand written screenshot, sorry for the mess, just to show it...
26. ### Voltmeter reading in a parallel circuit with two batteries

Homework Statement In the circuit below the batteries have negligible internal resistance and the voltmeter V has a very high resistance. What would be the reading of the voltmeter? Answer: 9.6 V. 2. The attempt at a solution I used the Kirchhoff's rule: the current that flows from 10 V is...

Homework Statement Resistor R1, R2, R3 are connected in parallel, have an equivalent resistance of 720(ohms). The currents are labeled I1, I2,and I3. I2 is 3x the value of I1, and I3 is 6x the value of I1. Calculate R1, R2, R3. Homework Equations I used the parallel circuit...
28. ### Series and Parallel Combination

[Note: Thread has been moved to the homework forums by a mentor] This is the Given problem This is my solution part 1 - What I did here is I series the R3 and R4 (R3 + R4), and I parallel the R34 to R5 (most of the calculation are from the calculator) This is my solution part 2 The...
29. ### Resistor parallel to short circuit when finding R_thev ....?

(sorry, I couldn't figure out how to insert an image from my drive) I have a problem where in finding the thevenin resistance I take out my independent sources and as a result I'm left with a resistor parallel to a short circuit. Should I ignore this resistor when calculating equivalent...
30. ### Solving voltage divider involving capacitors

Homework Statement Given ZV1 = ZV2 = 100Ω, ZCCV = ZCV = 2000/j = -2000j, and VV/VC = 0.04789. I'm trying to get the given VV/VC result. Homework Equations I know that 1/ZV = 1/ZV1 + 1/ZV2 + 1/ZCV VV = ZV / (ZV + ZCCV) * VC The Attempt at a Solution 1/ZV = 1/ZV1 + 1/ZV2 + 1/ZCV = 1/100 +...
31. ### LR circuit in parallel, need someone to check answer

Homework Statement L is a perfect inductor with inductance L. The switch is turned on at t=0 and the currents i1 and i2 run trhough the circuit as indicated by the figure. Homework Equations Given this circuit I need to find i1 and i2 for t=0 and t => infinity. The Attempt at a Solution For...
32. ### Can I Use Parallel Buck Converters to Achieve Higher Amperage?

I have a ton of 1A buck converters, and have a 5A application in which i need to run. I do not want to order any new buck converters, because I already have so many 1A ones, and do not have money for any new ones. Each one can only handle 1A before it over heats. I was wondering if I could use...
33. ### Potential difference of each resistor

Homework Statement What is the potential difference across each resistor? I know that I'll have to incorporate the V=iR equation but I don't know where to start though... My first attempt was with these: R1=4 R2=8 R3=5 R4=6 R5=3 24-I1R1-I1R2-I3R3+I4R4+I5R5=0 but this lead me nowhere so I...
34. ### Why is the voltage across this parallel circuit positive?

Homework Statement The problem along with its solution are attached in TheProblemAsWellAsSolution.jpeg file. For this post, I'm only referring to part (a), since part (b) is the same thing with another number. Homework Equations V = IR Parallel circuit: ##I = I_1 + I_2 + . . . + I_n## The...
35. ### Calculate the current between point A and B

Homework Statement [/B] What is the current between points A and B? The current I is unknown. The voltage is 12V. R1 = 3 Ohm R2 = 6 Ohm R3 = R4 = 4 Ohm Homework Equations U= R*I The Attempt at a Solution Total resistance from both branches: 1/R = 1/(R_1+R_3) + 1/(R_2+R_4) 1/R = 1/7 +...
36. ### Engineering Series and parallel circuit

Homework Statement Hello, can you help with this problem. For the next circuit, determine the voltages Homework Equations I=V/RT RT=R1+R2+R3+...+Rn P=V^2/R V=V1=V2=V3 I=V/R GT=1/R1+1/R2+1/R3+...+1/Rn The Attempt at a Solution My background is that I only know a very few and I don´t know how to...
37. ### Engineering Parallel Circuit Voltage Calculation: Solving for Voltages using Ohm's Law

Homework Statement Solve the next circuit to find the voltages Homework Equations I=V/R GT=(1/R1)+(1/Rn) V=V1=V2=V3 The Attempt at a Solution My background is that I know that in a parallel circuit, the voltage for each component is the same and electric current it's equal to the sum of the...
38. ### RL parallel circuit (AP 2006)

Homework Statement The circuit in the link below contains a capacitor of capacitance C, a power supply of emf E, two resistors of resistances R1 and R2, and two switches S1 and S2. After switch S1 has been closed for a long time, switch S2 gets closed at a time t = 0. Sketch graphs of the...
39. ### Induced EMF within a part of a parallel circuit?

A Power supply is connected to a parallel circuit with resistance R, there are three wires connected in parallel where the voltages would be the same,however, the current would be dived based on the number of wires and the resistance is the same. What would happen if wire (c) was placed in a...
40. ### Solar panels -- connect as parallel circuit or series circuit?

Hey, I have searched in the internet for the good or the negative points for a parallel- or a series circuit with a solar cell. But i didnt find something. I mean what is the difference when i connect many solar cells to a solar panel? What is better? A parallel or an series circuit? I know...
41. ### Engineering Current Flow in a Parallel Circuit

Hi, I'm taking a basic electricity course right now and I'm having trouble understanding a formula. The way they have their example makes no sense to me. Can anybody verify that their example is correct and explain a little bit for me? See attached file.
42. ### Parallel circuit problem

1. Consider a circuit with 3 resistors (250.0 , 150.0 , 350.0  ) connected in parallel with a 24.0 V battery. Find the total current supplied by the battery. Find the current through each resistor. 2. I=V/R 3. I know that resistors in parallel must be added up and then...
43. ### Engineering RLC Parallel Circuit: Solving for Current & Energy

Homework Statement See image Homework Equations .5Li2 .5Cv2 The Attempt at a Solution How do I calculate the current for a circuit of this type? I am unable to find any examples in our text. Can I use the following formulas to solve for the current flowing through each component: I(r) =...
44. ### Engineering RC parallel circuit, find the value of R and C

Homework Statement The circuit is a Parallel RC Z= 105KΩ∠-27 and Frequency is 50 Hz. I was given the following information and hints. 1/z = 1/R + jwc I need to find the common denominator of 1/R + jwc, Invert it to find z and simplify Z into one real and one imaginary part...
45. ### Engineering Solve RL Parallel Circuit: Find VL(0) Across 5ohm Resistor

Homework Statement Find the open circuit voltage VL(0) across the 5ohm resistor Homework Equations Z1*Z2/Z1+Z2 V(Z2*Z1+Z2) The Attempt at a Solution I thought for the open circuit voltage that due to infinite resistance of OC that the voltage across j35 inductor would...
46. ### Engineering Finding current in a parallel circuit

Homework Statement Determine IL in the circuit in the Figure. Figure: http://i.imgur.com/PvKXtjX.png V1 = ? Ix = ? IL = ? 3*Ix current source pointing downwards 7mA current source pointing upwards 7mA current source pointing downwards 7kOhm resistor 1kOhm resistor Homework...
47. ### Capacitor charge in series and parallel circuit

Homework Statement Three capacitors, with capacitances C1 = 4.0 μF, C2 = 3.0 μF, and C3 = 2.0 μF, are connected to a 12 -V voltage source, as shown in the figure. What is the charge on capacitor C2 ?Homework Equations Q=VC Q = charge V = voltage C = capacitance Ceq = equivalent...
48. ### Batteries in parallel circuit

I want to know how we can find out the net voltage of a circuit where two batteries with different voltages are connected in parallel... Let's consider the problem stated below... If I have a circuit where there are 2 batteries in parallel(5V & 15V)... And it is connected in series with...
49. ### RC DC Series and Parallel Circuit

Hi! Homework Statement Homework Equations V = IR Kirchhoff Current and Voltage Law. The Attempt at a Solution I am facing difficulty with this RC circuit. I tried looking up solutions but all I could find were either exclusively series or parallel. My first guess was to take Total Current...