A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit. Its basic function is to interrupt current flow after a fault is detected. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation.
Circuit breakers are made in varying sizes, from small devices that protect low-current circuits or individual household appliance, up to large switchgear designed to protect high voltage circuits feeding an entire city. The generic function of a circuit breaker, or fuse, as an automatic means of removing power from a faulty system is often abbreviated as OCPD (Over Current Protection Device).
Figure:
My attempt at a solution:
1st kirchoff law:
$$J=2I_0+I_0=6\, \textrm{A}$$
$$V_1+8=10\rightarrow \boxed{V_1=2}$$
$$V_1=6-V_S\rightarrow \boxed{V_S=-4\, \textrm{V}}$$
We are looking for ##P## generated in ##J##
$$V_J=V_1-2\cdot J=2-2\cdot 6=-10\, \textrm{V}$$...
Figure:
My attempt at a solution:
a) ##\boxed{V_{TH}}##
Current source equations ##\rightarrow \boxed{2=I_2-I_1}##
Control variable equations ##\rightarrow V_1=4I_2\rightarrow \boxed{0=4I_2-V_1}##
Super Mesh ##\rightarrow -0,5V_1+2I_1+I_2(4+8)-8I_3=0\rghtarrow...
What I have done:
The electromotive force due to Faraday's Law is: ##\mathcal{E}=-\frac{d\phi(\vec{B})}{dt}=\frac{d}{dt}(Ba^2)=a^2\frac{dB}{dt}=-10^{-4}V.##
In the circuit, going around the loop in a clockwise fashion:
##\oint_{\Gamma}\vec{E}\cdot d\vec{l}=-\frac{d\phi(\vec{B})}{dt}\Rightarrow...
I set up the equation ##V-iR-L\frac{di}{dt}=0##, with ##i(0)## and by solving it I got ##i(t)=\frac{V}{R}(1-e^{-\frac{R}{L}t})##.
Then, since the steady state current is ##i_s=\frac{V}{R}## I imposed the condition ##i(t_1)=\frac{9}{10}\frac{V}{R}\Leftrightarrow...
The figure is:
I have the solution to this problem:
We have two distinct branches
$$V_a-V_b=\overbrace{(V_a-V_c)}^{\textrm{INI}-\textrm{FIN}}+\overbrace{(V_c-V_b)}^{\textrm{FIN}-\textrm{INI}}$$
They have different intensities: ##3\, \textrm{mA}## and ##2\, \textrm{mA}##
##V_A-V_C\rightarrow##...
What I have done:
(1) ##I(0)=\frac{V}{R}=\frac{1.5}{25}A=0.06 A.##
(2) By setting ##I(t*)=0.06(1-e^{-(35/0.4)t*})=35 mA## we get ##t*\approx 0.01 s##
What I have done seems correct to me, but the result for part (2) should be different.
I would be grateful if someone could point out to me...
Hello guys, I am new here.
I was wondering whether I could get some help about the highlighted part. What I don't understand is why we are able to ignore the 5-ohms resistor when we have short circuited terminals a-b.
Thanks in advance.
So i used KCL and both currents are flowing into the node, and then leaving together to go to the resistor R3.
So my eq can be seen in the picture. I was looking in a book and they had a minus infront of the parantheses.
Is the current flowing from R3 into the node??
This the answer key::
im confused because it say "how much energy has been dissipated after 5s". So shouldn't you be looking at the ground after 5 sec.
but apparently the solution look at it before 5 sec, am I missing anything, can someone explain
I tried solving the part (a), and got I =1.82 A for the current value using Kirchoff's law.
Next, I want to use Ohm's law to calculate the voltage at point a.
Va = IR
In this equation, will resistance R correspond to 4.4Ω or 8.8Ω?
How do you determine which resistance to use when solving this...
In my lecture, it was explained that Kirchhoff's Rule is used when circuits are too "complicated" to simplify by combining resistances in series and parallel.
I do not understand in which cases I can simplify circuits by combining resistances, and on which cases I can only use Kirchoff's Rule...
The answer sheet assumes that the resistors in both circuits are in series and that we need to use the equation Req = R1+R2+R3.. to find the Req in both cases. How come the resistors are in series, when there are multiple resistors in a single row?
Also, why does the following work yield the...
Given the following input parameters:
Parameter
Value
Rs (Resistance through stator)
1.4 Ω
Rr (Resistance through stator)
0.7 Ω
Ls (stator inductance) = Lr (rotor inductance)
0.002 H
xs = xr = 2*π*f*Ls
0.6283i Ω
Lm(magnetic inductance)
0.01 H
xm = 2*π*f*Lm
3.1415iΩ
f (frequency)...
I'm completely new in hobby electronics, and I assembled the following circuit to control a power LED over wifi using esp8266. The problem is, that it is always, on and sometimes flicker , no matter,what I send via GPIO1 port. I know that this is not an esp8266 problem, I tested my program with...
I was following these [steps](https://www.allaboutcircuits.com/textbook/direct-current/chpt-10/delta-y-and-y-conversions/).
I was calculating resistance for left side circuit.
$$R_1=\frac{2 × 2}{2+2+4}=0.5\Omega$$
$$R_2=\frac{2 × 4}{2+2+4}=1\Omega$$
$$R_3=\frac{2 × 4}{2+2+4}=1\Omega$$
Then...
why does the voltage of the capacitor eventually go to 0 when discharging the capacitor? I heard that's because "current starts flowing when discharging", but how exactly does that lead to V going down? I know that I = C * dV/dt, but that doesn't seem to help me understand why V goes down (which...
Homework Statement:: A K-type thermocouple is connected as shown to sense temperature. The temperature zone is at 25°C. The RTD has a resistance of 100 at 0°C and a TCR coefficient of 0.00385. A 5V power supply drives the circuit. Calculate R2 for proper compensation. What is the emf produced...
The main problem is the verse of the 2 currents ## i1 ## and ## i2 ## . I think they both go clockwise, so in the node A we should have ##i1+i2=20A##. Now let's apply the second law (going clockwise). So ##ΔV1-R1*i3 - R2*i4 + ΔV2=0##, where ##i3## and ##i4## are the currents which pass through...
First when it is connected to the battery, the capacitors start accumulating charges such that the potential difference equals that of the battery. Then the current stops flowing.
##Q_1 = CV##
##Q_2 = nCV##
Where 1 and 2 represent the capacitor with capacitance C and nC respectively
Then, when...
Let us connect a battery of potential difference V to a wire. There is no resistance. Nothing!
Now the battery creates some potential difference and the charges in the conducting wire move due to the Electric field created in the conductor by the battery. So, as the charge moves, its potential...
I am trying my hands on building receivers and transmitters. For now I would like to build this receiver here:
now I see that the 500pH inductor in parallel witht he 200uH capacitor are in charge of filtering the unwanted frequencies. The top-left NPN is in my guess an emitter follower to...
I am close to graduating as an EE major but I have never been able to organize a step by step method on analyzing a circuit. It seems to me that every time I am trying to analize a circuit I end up with a bunch of equations and nothing more. I know that I should:
1. Know what I am solving for...
I am trying to create a receiver for a personal project I am working on. This is the RF amplifier that I was given by a book I am following. How does this circuit work? Usually for a BJT amplifier I find the DC bias point and then use the small signal model after I bias the circuit? I understand...
Here is a circuit diagram:
.
We have three capacitors, with capacitances ##C_1##, ##C_2## and ##C_3##. Plates are labelled as ##A_1, A_2, A_3 ... A_6##. Point P is connected to the positive terminal of the battery and point N is connected to the negative terminal of the...
I need to find A_v, I want to relate Vin to Vout. To do this I did KVL on the major loop:
$$V_{DD} = I_D*R_D + V_{SD1} - V_{SD2} - I_D*R_D$$
Since M1 = M2 then everything would cancel out and I would just get V_dd = 0 which is probably wrong. This is assuming V_sd1 = V_sd2, is that correct?
I know how to calculate the power output and input by analyzing the current in put and output with multimeters and using the formula P=VI. But P_out is obviously incomparably smaller than P_in so the efficiency would suck this way. Is there a better way to do this??
Hi.
Let's say we have a circuit like that, and we want to find the Thevenin/Norton circuit from a and b points.
So for Vth, we calculate the Voc, in which we remove the 2K ohm resistor and calculate the Voc. I calculated it correctly. But I have problem in calculating the Norton current. So in...
I tried to conserve the charge on the left plates of both the capacitors as intially the total charge on both is 48 and at t=t0 the total charge is 36(on c1) +4V(V is the potential across c2) so i got V=3 and then i conserved the energy
Initial energy on both capacitor = final energy on both +...
The voltage source in the circuit below has been switched on for a long time when the switch S switches off. How long will it take before the current coming out of the capacitor has become less than 1 mA?
My attempt:
I am far from sure that my solution is correct. This is because i...
Homework Statement:: How can I determine whether my basic circuit will work? A battery and two light sources.
Homework Equations:: conceptual question, use basic ohms law, current law, voltage law, etc.
This is not a homework question, i am just trying to understand electronics better. I am...
I have no problem getting the ##R_{TH}## since from the special element's POV, the resistors are in parallel, and that's the answer.
However, I don't really understand how to get ##V_{TH}##.
Ignoring the special element, it seems that I have the resistors in series this time. But I'm not too...
I don't really understand or see the correct way to approach this.
Letting the current in question be ##i_x## (as shown in Fig. 1), and the unknown (changing) resistance be $R_x$, I can write:
##-V_s + R_s i_s + i_x R_x = 0##, and ##R_p i_p = i_x R_x##. Hence we can also write ##-V_s + R_s i_s...
I am going through "Circuit Analysis for Dummies". On pg 18, it says, "If you calculate the power dissipated as 0.1 watts, then a 0.25-watt resistor can handle this amount of power. A 0.125-watt resistor should be able to handle that amount as well, but when it comes to power ratings, err on the...
I already found ##I(t)## using Kirchhoff's laws, I got the equation ##V-RI-L\frac{dI}{dt}=0\Rightarrow L\frac{dI}{dt}=V-RI## then I solved the differential equation getting ##I(t)=\frac{V}{R}\left[1-e^{-\frac{R}{L}t}\right]##. My problem is founding the voltage as a function of time ##V(t)##, I...
I tried to solve it by loop currents. So on the left mesh the loop current ##I_1## goes clockwise and on the right mesh the loop current ##I_2## goes counterclockwise.
I ended up with the following equations:
1) ##V_1-R_1(I_1+I_2)-R_2I_1=0##;
2) ##V_2-R_3I_2-R_1(I_1+I_2)=0##.
To find the...
Hello everyone,
I am in an upper division undergraduate electronics and circuits class right now and the textbook that were using (Eggleston: basic electronics for scientists and engineers) is not resonating with me. I was wondering if anyone had recommendations for a textbook that explains...
The open loop voltage gain is given as :
$$ u(s) = \frac{u_o}{1+\frac{s}{w_o}} = \frac{100}{1 + \frac{s}{40}}$$
Where u_o is the d.c. voltage gain and w_o is the pole.
The op amp that is given is:
And I am told to use the non ideal op amp model as follows:
Well my guess is that I can...
A sketch of the setup and the equivalent circuit are attached.
I believe the correct way to solve this is to redraw the circuit as shown in Fig. 3 and then remove the connections between evidently equipotential points, which reduces the problem to a familiar setup of in parallel and in series...
The circuit to be analyzed is shown below:
Since initial conditions are zero (from the instructions) I will use laplace transforms for the cirucit and I will use the MAME method to solve this circuit. The laplace transforms that are required will give me:
$$E_g(s) = \frac{10}{s}$$
$$ L_3...
Summary: Facing a circuit with 2 parallel resistors and 2 current sources (1 dependent, 1 independent). Trying to find the current, voltage, power delivered by the independent current source and power delivered by the dependent current source.
I'm trying to start by finding the current i0 but...
Hi all !
I want a confirmation for this exercise please.
The circuit:
This is my try: https://www.docdroid.net/EFuTDMp/new-doc-2019-10-03-234340-1-converted.pdf
--
Thanks
What forces are acting on electron in a circuit?
What is the source of such kind of forces?
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If i have an ordinary electric circuit with only one resistor, then if i raise resistance, the electric current goes down. As I understand it happens...
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