Rl circuit Definition and 133 Threads

Homework Statement Homework Equations τ = L/R The Attempt at a Solution So I already know the initial current and final current (-4mA and -1mA, respectively), my question is how I would find the resistance value to use to solve for the time constant. After the switch has been closed for a...

Homework Statement Homework Equations The voltage across an inductor is V(T) = L i' Basic current division and voltage division . Step function where u(T) : when t is smaller than 0 : u(t) = 0 t >0 : u(t) = 1 The Attempt at a Solution The voltage source has...

What happens when the switch closes? Does the inductor continue to charge? If yes, how can this be so when the inductor is already fully charged (the question says the switch was open for a long time, so I assumed it has been fully charged)?

Homework Statement Image Homework Equations KCL DRIVEN RL CIRCUIT The Attempt at a Solution I got the right answer after trying a different tactic, but I don't understand why it is done this way. My first approach: KCL: 100/45 + 60/2 = iL for t < 0 32.22 -...

Homework Statement Image Homework Equations Current divider The Attempt at a Solution The only thing I see is that I solve for R1 and R2 for t < 0. Other than that I'm confused and not even sure I'm right about solving t<0.

Homework Statement a) A circuit contains two elements, but it is not known if they are L, R or C. The current in this circuit when connected to a 2.16×102 V, 60.0 Hz source is 6.10 A and lags the voltage by 3.60×10^1 degrees. What are the two elements? c) What is the power dissipated in...

Homework Statement A 5.0V battery is attached to an RL circuit. The current is given by the formula: I = V0/R(1-e-t/τ), where I0 is the steady-state current, and τ is the time constant for the circuit. Using the data table provided, determine τ, R, and L for this circuit. I(mA) | t(μs)...

Homework Statement Homework Equations The Attempt at a Solution I understand everything except how they got i(∞). It seems like they used current division on 3A. But where are they applying current division and where did they get 3A? Also, in the last step, they magically added u(t). Where...

Homework Statement Homework Equations The Attempt at a 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 have this solution: I don't understand where they got that...

Homework Statement Consider the RL circuit shown in the figure. Assume that the current ##i(t)## has reached a steady state with the switch at position ##A##. At time ##t = 0##, the switch is moved from position ##A## to position ##B##. http://imgur.com/dRIOrp0 If I use the image button...

Homework Statement The circuit is in steady state before the switch is closed at t=0 I need to find how the current changes with time after the switch is closed. The Attempt at a Solution I read that at steady state inductor behaves like a short circuit, so does this mean when the switch...

Homework Statement Find the expression of the current "i" by terms of time. The answer is 3e^(20t) Amps Homework Equations i(t)=I_final+(I_initial-I_final)*e^(-t/τ) The Attempt at a Solution I have found the initial current as 3 amps. However, after the switch had been changed for too long...

Homework Statement An inductor with L = 50 mH is in series with a resistor of R = 180 ohms. At t = 0, a potential difference of 45 V is suddenly applied across the series circuit. At what rate is the current increasing after 1.2 milliseconds? Homework Equations V = IR + Emf Emf =...

Question 1 Homework Statement For a circuit show on Fig B1, what is the rate of change of the current in the inductor when the total current in the circuit is 0.50 A? (L = 10 mH, R(1) = 10 ohm, R(2) = 20 ohm, V = 12 V). In the figure the resistors of the circuit are in series. Ans: 200...

Homework Statement I have to calculate first commutation process (t=0) and second commutation process (t1 = 2*τ) Both swithes are closing in the given time moment. Homework Equations Form of second commutation process: The Attempt at a Solution I have already calculated...

Hi.. This is sundaram, I'm trying to learn state space modeling, I'm trying to model the simple RL series circuit, to control/read the current flowing through inductor. I could find the way to monitor the voltage across inductor. as below x'=(u - Rx)*(1/L) y=(u - Rx) where: x => i...

If I have a circuit with R = 1Ω L = 300μH V = 20V i0 = 5A I know that I can use the equation at the bottom of page 13 to calculate the current rise given any starting current and input voltage: i(t) = (V/R)[1-e-t/τ] + i0e-t/τ This is fine, and stops increasing at 20A as expected...

Homework Statement Task is to write differential equation for this circuit. E, R1, R2, R3, L are constants. Homework Equations Ul = L di/dt The Attempt at a Solution I guess, we have to use current method for each contour. 1st contour equation: E = U1 + U2 + Ul =...

Homework Statement There's a DC supplying a current V over resistance R and inductor L in parallel. The circuit looks like this except it's DC http://sub.allaboutcircuits.com/images/02262.png I need to find the total current. The Attempt at a Solution I know that the current through the...

Homework Statement At the moment t = 0, a 24.0-V battery is connected to a 5.00-mH coil and a 6.00-V resistor. (a) Immediately thereafter, how does the potential difference across the resistor compare to the emf across the coil? (b) Answer the same question about the circuit several seconds...

Homework Statement There's a coil, resistance R=7Ω, and inductance L=1mH, and its powered by a generator with variable frequency and Vmax=10V. At what frequency is inductive reactance equal to resistance? (when z=R√2) Homework Equations z=R√2, z=√(R2+(ωL)2) The Attempt at a...

I fully understand mathematically using differential equations and also using conservation of energy why current should decay in an RL circuit. However , I cannot comprehend how this phenomenon can be explained purely based on induced voltages and currents. An intuitive understanding basically...

Homework Statement A step input of 100V is applied to a resistor of 50Ω in series with an inductor of 10H at time t=0. Calculate the time at which the voltage across the resistor equals the voltage across the inductor Homework Equations Im not sure which equation to use, i know τ=L/R...

Homework Statement The current in a series RL circuit increases to 20% of its final value in 3.4μs. If L = 2.0mH, what is the resistance R? Homework Equations I=I_0(1-e^(-t/(L/R))) <----Im not sure if this equation is right? The Attempt at a Solution I'm unsure how to start...

Homework Statement See attachment. Homework Equations V(t) = Vmcos(\omegat + \theta) P(t) = VmImcos(\omegat + \phi)cos\omegat PR(t) = \frac{V^{2}(t)}{R} PF = \frac{P}{VeffIeff} S = VeffIeff Pavg = Ieff2(Re(Zeq) The Attempt at a Solution (a) Ieff = 5 A f = 50 Hz or \omega \approx 314 rad/s...

Homework Statement I have the following parallel RC circuit. At time T = 0, the switch will close and the circuit will be connected. We assume that prior to T = 0, the circuit was at a steady-state. I want to calculate VL(t) -- but I am being told that this is not possible for this...

Suppose a circuit with resistor R and inductor L with no source. I am trying to find kirchhoffs equation for this circuit - I am getting iR -Ldi/dt = 0 as my equation which is apparently wrong. I just cannot understand how do I make equations for such circuits.

Hi, Was hoping someone could help me. I have the following RL circuit: 20V input 8.2kohm resistor and 50mH Inductor in series. Determine time constant: I answered with: T = L/R 50mH / 8.2kohm = 6.09 uS Is this correct? The question I am stuck on is: Determine the...

Hi all, I'm taking a fourth year time-series analysis course for Physics students. Homework Statement Let us consider a simple physical system consisting of a resistor (with resistance R) and an inductor (with inductance L) in series. We apply an input voltage a(t) across the pair in...

Homework Statement The Attempt at a Solution V-R_1I_1-LdI_L/dt=0, V-R_1I_1-R_2I_2=0, I_1=I_L+I_2 My result is I_L=(V/R_1)(1-exp[-tR_1R_2/(R_1+R_2)L]) Where is my fault? Any help is appreciated!

any help would be much appreciated i am trying to calculate the inductance and impedance of a unknown air cored inductor. over a set frequency range (1600hz - 2700hz in 100hz increments) using a series RL circuit tools scope multimeter frequence generator Amplifier 1ohm 100W metal...

I'm stuck at part (a) of this question: http://i.imgur.com/9IqKu.png It seems that the source is DC voltage, and since the inductor acts as a short circuit in DC, Vo is basically 1000V? So the sketch is basically a straight line? Is there something I'm missing here?

Hello I have the following calculations to do. An inductor of 10H and 25 ohm resistance is connected in series with a 75 ohm resistor and Vs=240 V DC. 1. the time for current to develop maximum current. so what I did is that: Max current is I= V/R= 240/(25+75)= 2.4 A And time constant T= 0.1 s...

Homework Statement A circuit made with a battery, a switch, an inductor. and three resistors is shown in the figure. To begin with, switch S has been open for a long time. Then at time t = 0 the switch is closed. http://i.imgur.com/ws5UD.png After being closed for a long time, the...

Homework Statement An inductor initially has 3 A of current passing through it at time t = 0. The current through the inductor increases at a constant rate until 5 A of current is flowing through it 1s later at t = 1 s. The voltage across the inductor is 4 μV while the current is increasing...

Homework Statement http://i.imgur.com/22jq3.png Three identical resistors are connected to a battery, an inductor, and a switch as shown in the figure. (The values of all circuit elements are given below the figure.) The switch has been open for a very long time, and then it is closed...

Homework Statement [PLAIN]http://img14.imageshack.us/img14/4355/screenshot20110807at249.png Homework Equations v(t) = Vmax * e^(-Rt/L) i(t) = imax * e^(-Rt/L) P = V^2/R w = integral of power w/ respect to time w(0) = .5Li^2(0) = energy stored in inductor The Attempt at a...

An inductor “L” is connected in series with a Resistor “R”. This circuit is connected to a sinusoidal voltage “V”, and a current of 1A flows. If the circuit resistor has a value of 1W, and the magnitude of the reactance of the inductor “L” is 1W at the supply frequency, state: (i) The...

Im starting to give up on this one, every time i try to figure it out i get an answer that is miles off. Im looking to find ZL, can someone show me how this is done? I think my problem is with the dependent voltage. http://img31.imageshack.us/i/unledak.png/

Homework Statement I have to show that the impendance of a parallel RL circuit would be the same in measure as the impendance of a non-parallel RL circuit (sry, don't know how to express this in English). I have to show this so that the inductivity stays the same in both cases but the...

Homework Statement Find i0(t) see attached pictureHomework Equations io(t) = iinfinite + (i0- - iinfinite)e-Rt/L The Attempt at a Solution I first re-drew the diagram for when the switch has NOT been closed, which is esssentially the same thing without the 37.5 V Source and the adjacent 10...

Homework Statement What is the inductance in a series RL circuit in which R = 7.0 kΩ if the current increases to one half of its final value in 26 µs? Homework Equations am i correct in assuming that i should be using the time constant equation: Tau=L/R The Attempt at a Solution...

http://img713.imageshack.us/i/39642770.jpg At time t = 0_ The circuit looks like the voltage source in series with R1 and R2 with the inductor acting like a short circuit. iL (0_) = 60V/50Ω = 1.2A At t = 0+ The circuit looks like http://img839.imageshack.us/i/52735488.jpg...

Here is the circuit: http://img840.imageshack.us/f/60205514.png/ I need to find: I Z VL - Voltage on Inductor XL L I have I and Z but I can not figure out VL, XL, and L. This is what I have for I and Z: ----------------------------------------------- a.)...

1.http://s1191.photobucket.com/albums/z462/havoc0040/?action=view&current=21prob42.jpg The switch in the figure is open for a very long time and then closed at t = 0. What is the current through R1 immediately after the switch is closed? ( Use V = 3.5 V, R1 = 848 , R2 = 548 , L = 7.2 mH )...

Homework Statement find total impedance of a circuit with R1 and L in parallel with R2. circuit looks like this (but with R2 instead of C): http://wpcontent.answcdn.com/wikipedia/en/thumb/7/75/RL_series_C_parallel.svg/160px-RL_series_C_parallel.svg.png Homework Equations formula for two...

Homework Statement An emf of 10V is connected to the RL circuit (R = 10 Ohms, L = 1.0 H) shown below for long, long time (the switch is in position 1). Then, at t = 0 the switch is thrown into position 2. Find the current in the circuit at t = 0.2 s. When will the current drop to 0.001 A...

Homework Statement Basically, I am deriving the following equation: I=I_0(1-e^{-\frac{R}{L}t}) Homework Equations 1) L\frac{dI(t)}{dt}+I(t)R=V 2) \frac{V}{R}=I_0 The Attempt at a Solution In relevant equation 1), R was divided both sides, and by using 2), I turned it into...

Hi Guys, This is going to be a bit controversial but that's ok. In an RL circuit, both with and without a battery, Kirchoff's law is invoked in virtually every elementary textbook in the United States and perhaps in the world. It is a mistake! The voltage drop across an inductor is...

Using Kirchhoff's rules for the instantaneous currents and voltages in the two-loop circuit, find the current in the inductor as a function of time. I used Kirchhoff's rule on the left loop consisting of the battery and the right loop which consist of the inductor and gotten the following...