Tagged Questions

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Circuits and Power

"The diagram below represents a simple circuit composed of 5 identical light bulbs and 2 flashlight batteries. Which bulb (or bulbs) would you expect to be the brightest? a) V only b) V and W ...
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Ohms Law Voltage/Potential Difference [duplicate]

Three 2.0 Ω resistors are connected in series to a 12 V battery. What is the potential difference across each resistor? � This question requires Ohms law because V is needed right? So I would use I = ...
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Circuit problem: Kirchhoff's current law [closed]

For this question, I try to use this three formula to solve it. $30 = 13I1 +18I2$ $24 = 5I3 - 18I2$ $I1 = I2 + I3$ Am I correct? Please advise me.
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Phasor Diagram with AC circuits [migrated]

Suppose you take a 2.0×102 resistor and a 0.40 inductor and make a series circuit with a voltage source that has voltage amplitude 30 and an angular frequency of 2.5×102 . **Part F (The part that I ...
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Finding the voltage of an inductor in a RL series circuit [closed]

Here is the solution: This assigned question is an odd one since it doesn't seem to have anything to do with phasors which is the chapter I am currently studying. I know that that the phase ...
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Weird resistor patterns [closed]

I came up with the following question: The vertices of tetrahedron ABCD are all connected by 1-ohm resistors. What is the total resistance between A and B? I haven't the faintest idea how to ...
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Is this way of solving Thevenin theorem correct?

This thevenin theorem is really giving me a headache, and I've really searched many sources in the internet but they confused me more and more. Take this as an example: The guy in the above link ...
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I want to know that if in a Wheatstone Bridge ,that is made of capacitors only we have this condition $c_1c_3=c_2c_4$. The $c_5$ capacitor would be dead and it's voltage would be zero? Actually I ...
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What is a non-linear capacitor?

I'm new here. I have a (maybe dumb) question: What are non-linear capacitors? I'm given a circuit including a capacitor and the question says The given capacitor is non-linear with the ...
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Charge Amplifier response and frequency response [closed]

I am getting ready for my final and have completed everything on my study guide except for two questions I cannot figure out. Here is the first question: I have gone through all my lectures and ...
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Kirchoff's rules and RC circuits [closed]

You can view the image bigger: http://i.stack.imgur.com/4moUP.png I'm studying RC circuits and I can't understand the part when we use Kirchoff's rule. When working with batteries, when we're ...
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If you have $N$ 1ohm resistors, how many distinct equivalent resistances can you create?

If you have $N$ 1ohm resistors, how many distinct equivalent resistances can you create? Assume that only parallel and series and mixture of them is allowed and no bridging between two parallel ...
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electric current in parallel circuit [closed]

If I have a parallel circuit with two resistors ($R_1=48 \Omega$ and $R_2=16 \Omega$) - and $R_1$ has a $0.1 A$ current running through, is it possible to calculate the current through $R_2$ without ...
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Power dissipated through resistor in RC circuit with charged Capacitor [closed]

so here's the problem: A simple RC circuit where the capacitor has been charged, and two resistors are in parallel configuration. How does one find the power (as function of time) through any of the ...
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Current through two inductors after a long time

I'm having trouble with visualizing the following problem, which is asking me for the final, steady current in both inductors $L_{1}$ and $L_{2}$. I was thinking that after a long time, essentially ...
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How to Determine the voltage polarity of inductor in a circuit? [closed]

The Voltage polarity across the inductor is same as that across the capacitor since both are in parallel and the voltage across them must be same. But when Inductor, capacitor and resistor are ...
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Kirchoff Loop and current

The pic of the circuit/problem: I got the problem right, but i want to make sure my reasoning is correct for the current left of the 2.1 V battery. Its the same current as $I_1$ because the ...
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Wrong positioned Ampere-meter and Voltmeter [closed]

I'm dealing with a problem here and even that I'm trying to solve it i can't It says: In what figures the voltmeter and ampere-meter are wrong positioned? I think that all the the others are ...
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Different phase in capacitively coupled RLC circuits

I was trying to work with some data for a lab report I'm writing about capacitively coupled RLC circuits. The setup is pretty simple and looks like that: Where $C^{'}$ is the coupling capacitance. ...
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Is R1 R2 and R3 parallel? [closed]

or R2 and R3 are parallel then they are in series with R1?
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Balanced three phase circuit Y-Y with neutral

Here is my equivalent balanced three phase circuit Y-Y with neutral: Rla + jXla is my line impedance by phase. L1 and L2 are my loads. The exercise is saying that L1 absorbs 180 W and 240 VAr, L2 ...
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How to get a function for the voltage across a capacitor connected to an AC voltage source? [closed]

I am looking for the way of obtaining a solution for $V_{c}$ ,as a function of $t$ depending of $\omega$, of the following differential equation related to an electrical circuit involving a low-pass ...
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How to find power factor value of parallel RL circuit knowing the power factor value for the series circuit with the same components

Because I know the value for the power factor for the series RL circuit I've tried to find the ratio between the series circuit power factor and the parallel circuit power factor, expressed in terms ...
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Resistor connections [duplicate]

I can't figure out what kind of connection it would be if i put resistors like this Can someone please explain how they are connected, like is R1 and R2 in series and R4 and R5 in series and then I ...
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RLC circuit, turning off the voltage source

An RLC circuit (pictured above) is governed by two equations: $$-iR=-L \frac{dj}{dt} = \frac{q}{C}+V(t)$$ $$\frac{dq}{dt}=i+j$$ q satisfies the equation: ...
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Need to find the Vab of this circuit! [closed]

Find Vab in the circuit http://imgur.com/IqZ7Yis I uploaded a picture of the circuit. I tried adding 10 and 5 (top) because they appear to be in series. I also added 10 and 15 (bottom two) because ...
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How do I combine three resistors which are in parallel with each other?

For this circuit (a and b are connected by a battery), Will I be able to find the total resistance of the circuit by adding resistors that are in series and combining resistors that are in ...
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Solving circuits using kirchhoff's laws and elimination method ( not any matrix method) [closed]

I need to solve this problem as part of my review in college physics. The task is to find the value of 5 branch currents using Kirchhoff's laws and elimination method (or maybe called elimination by ...
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Where is the mistake in the following DC circuit analysis? [closed]

In the following circuit, I'd like to calculate the potential difference $V_{BA}$. One way is to solve the circuit, by calculating all the currents $I_1, I_2, I_3$. The system of equations is: ...
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How to calculate potential in circuit

In the following circuit (that has come up during a BJT DC analysis for what is worth), I'd like to calculate the potential at point B and point E. My notes say that $V_B = -10 + 0.7 = -9.3V$. ...
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How to convert RL Circuits? [closed]

How do we convert a parallel RL circuit into its equivalent series RL circuit ?
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Capacitors in parallel and dieletric [closed]

I'm trying to solve this problem: Two capacitors of capacitance $C_1=200pF$ and $C_2=1000pF$ are connected in parallel and loaded to a potential difference of $400V$. Subsequently the space ...
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Unbalanced wheatstone bridge

Suppose I have an unbalanced Wheatstone bridge (resistances $R_1, R_2, R_3, R_4, R_g$), to which I apply some voltage $V$. I need to find the voltage across the the galvanometer. Solving the system of ...
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Applying more current? [closed]

An electric motor draws 20 Amps, when at maximum load of x. Can that value of current be applied even if the load was ten times less than x from a certain power source?
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Variation of power factor with impedance in a series RLC circuit

I am solving this problem from a previous year question paper A series RLC circuit has resistance of 1k at resonant frequency and half power frequencies are 20kHz and 100kHz. Determine (i) The ...
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Help with inductance and a moving (rolling) rail problem

I can't even do the first part. I've exhausted just about every direction. I've done plenty of moving rail problems without rolling, but I'm guessing you have to have some relationship between the ...