Impedance Definition and 488 Threads

Homework Statement I am given the following circuit: and asked to solve for v(t) and i(t) Homework EquationsThe Attempt at a Solution If this is right, I don't know where to go from here.

Homework Statement Find the impedance as seen by the source. Homework EquationsThe Attempt at a Solution -j2||j1 = 2i Z = 2-j1+j2+(1^2)/(j2+2+j2) Ztotal = 2.1+0.8i Is this correct?

I've searched high and low for data regarding this from scientific papers to books and I cannot find anything in regards to the approximate impedance to excite a vacuum vessel to plasma state. In particular I want to built a RF Plasma cleaning chamber, however, I am not sure how to design the...

Homework Statement https://scontent-lax3-1.xx.fbcdn.net/v/t34.0-12/14804959_10155526179417281_80533891_n.png?oh=649ee14155ac558b21c6553f003e418b&oe=5809EAA0 Homework EquationsThe Attempt at a Solution 1) I determined the input impedance of the first transmission line (Zin1). 2) I calculated...

Hello. Homework Statement What is the impedance of a circuit in which resistor and inductor are connected in series with each other, and a capacitor is in parallel with them? How should I sum the voltages in order to find the impedance? 2. Homework Equations V = IZ IZ = VR + VC + VL ? The...

Homework Statement Find the impedance (Z) of the circuit in the shown figure (R and L in series, and C in parallel with them). A circuit is said to be in resonance if Z is real, find ω in terms of R, L, and C? Homework Equations VR= RIeiωt VL= LiωIeiωt VC= (Ieiωt)/(iωc) What I mean by I is I...

Homework Statement Referencing the attached picture: a) Show that the RMS current in the 1 kΩ resistor is 6.5mA. b) If the AC voltage source was replaced by a battery, what would the current in the resistor be? Homework Equations V = IR Z = √(R^2 + X^2) The Attempt at a Solution To begin, I...

My name is Jackson Richter. I am retired from Rockwell-Collins and worked in the engineering lab for 31 years. Since my retirement my interested have peaked in radio communications. Especially in antenna design. Thanks to anyone here that would give me a little more insight with my...

I am a bit confused on source impedance and Tline impedance, when both are equal. Let's say source impedance is 50 ohms and Tline imepdance is also 50 ohms. Why does the incident wave divide between the source impedance and tline impedance. The impedance is same, so reflection co-efficient...

Is it possible to combine (possibly infinite) capacitors and inductors to get a total impedance which is independent of frequency. If so, how?

Homework Statement imgur link: http://i.imgur.com/0Zc8nQe.png Homework Equations Y-Delta transformations The Attempt at a Solution Since it's a proof, I can't check the answer in the back. What I did: I transformed the three impedances in their delta config to a Y config, and my TI89...

Homework Statement Calculating the open loop output Impedance at 1kHz and the open loop differential gain The Attempt at a Solution Here is the approach. INPUT STAGE: Q111 and Q112 Av1 = Rtot/2re, where Rtot is the total resistance of R117 and the input resistance of Q78 which is Rin. So...

When an alternator is supplied with a 3-phase voltage and its rotor is rotated in opposite direction to that of the stator rmf, the ratio phase voltage/phase current is the negative sequence impedance of the alternator. My understanding of this is as follows: When rotor is rotated in opposite...

Hello, I'm confused about the concept of impedance matching in regards with hydrophones and DAQs. If the input impedance to an ADC channel on a DAQ is very high, would I need whatever's being fed into it (hydrophone) to also need a high impedance? Or would it need a low impedance? I've tried...

I assume the 10X setting to be the most useful with audio work. Comments?? My oscilloscope has 1M ohm input impedance when set at 10X as stated above. What is the likely impedance at 1X ? The manual indicates the above chart is based on the probe being set at 10X. As I am dealing with DC...

Homework Statement I need this to find the the reflective coefficient and multiply this by 100 to find the percentage of original energy reflected back however i cannot find the acoustic impedance of wool no matter how hard i try. Homework Equations Im using the reflective coefficient formula...

Homework Statement Hello, long story short: I need to create a model of Li-Ion battery and I'm stuck on calculating the battery equivalent internal impedance. The thing is, I don't know the equation or even how to make one. However, I have a circuit drawing: Homework Equations Values in...

I was wondering, at high frequency circuits, when the lumped circuit model must be used, why does impedance depends on the position in the wire? By the way, it's my very first post here =D

Homework Statement This isn't so much of a problem itself but I found it interesting that on the All About Circuits website, two of the questions give a phase angle for impedance as opposite the angle of current. I understand the current is 90 degrees out of phase with voltage in both RL and RC...

Homework Statement A series RLC circuit consists of a 60.0 Ω resistor, a 2.30 mH inductor, and a 690 nF capacitor. It is connected to an oscillator with a peak voltage of5.80 V . Part A Determine the impedance at frequency 3000 Hz. Part B Determine the peak current at frequency 3000 Hz. Part C...

Hi everyone! As a Belgian student electrical engineering, I am going to Peru this summer with Humasol vzw, a development organisation that works with engineering students. Our job is to build a hydro turbine next to a small river to provide a little community with electricity. Also part of our...

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 +...

I do not understand how to solve capacitors and inductors with impedance. I do not even know what it is that they use it to solve for. My understanding is that the define the source as a sinusoid using the complex exponential form, and that all voltages and amperage are now also complex...

Homework Statement Hi would somebody please be able to check to see if my workings look good? Homework Equations 1/Z=1/Z1+1/Z2 IF Z1 = 3 + J2 and Z2 = 1 - j3, calcualte Z giving your answer in the form r(cosθ + jin son θ) where θ is in radians The Attempt at a Solution Attached as a...

I built a voltage amplifier based on the AD625 instrumentation amplifier. This chip has a 1 G-Ohm input impedance. When the load has a resistance of 100 kOhm, output drift is negligible. When the load has a resistance of 100 MOhm, output drift is significant and not acceptable. Are there any...

Homework Statement A real voltage source can be expressed as an ideal voltage source that is in series with a resistor that represents the inner resistance of the voltage source. This voltage source is a EMF and it is also in series with another resistor. Suppose both the EMF resistor...

Hi Anyone know of an online asymmetric differential stripline impedance calculator? I already have the Saturn pcb design tool kit. I just want to find a second one to cross check the result. My experience is I have seen two calculators gave different results. Thanks

For a plane wave traveling in free space we know from Maxwell's equations that: Z= E/H=√μ0/ε0 = 377Ω The meaning of the wave impedance is that if we have an electric field oscillating with amplitude E0 in a medium (in this case the vacuum) a magnetic field will be induced with amplitude E0/Z...

I know FET offers a very high input impedance..but what's the reason behind it? Is it due to the reverse voltage applied at gate with respect to the source which makes the P-N junction reversed biased? If that the case, what happens when there is no voltage applied at gate?

Homework Statement Find Norton current and impedance between points A and B. Homework EquationsThe Attempt at a Solution I really don't have idea how to find impedance when points A and B are positioned like that in the diagram. And if let's say I found the impedance , when trying to look for...

Homework Statement Find the maximum power on a impedance Z. Homework EquationsThe Attempt at a Solution I got as Thevenin impedance Zt=4+j4 and Ut= 32 V, but since my solution for power is wrong, something is wrong with either impedance or voltage (or both). If point A is above Z, and point B...

Hi everybody. I am trying to understand the concept of impedance matching and tuning of RF coil. As far as I understand there are 2 stages: At the first stage I should match the coil to the source (Let's say with L network method) and the second stage is to tune coil to the desirable frequency...

Hi everybody. I am trying to understand the concept of impedance matching and tuning of RF coil. As far as I understand there are 2 stages: At the first stage I should match the coil to the source (Let's say with L network method) and the second stage is to tune coil to the desirable...

Homework Statement Hello, I just came across a design problem based on an inverting op amp. The requirement output values are -25G and not greater than 1kOhm output impedance. With inputs 1V p-t-p and 75Ohms input impedance Choosing values for the gain seem fairly easy, but how these values...

Homework Statement Hi everyone, I'm just having a little trouble with equivalent resistance in a bridge, in the image I attached. The textbook says that the way to solve this is to put R3 and ZL2 in series, that series is in parallel to the short circuit in diagonal, and then at the end we...

I was calculating the impedance of a capacitor and inductor of ## 1 \mu {\text F}## and ##1 {\text H}## respectively, at ##1000 \frac {\text rad}{\text s}## in both series and parallel configurations. I found the impedance to be 0 and infinity in the two cases, which is correct. But now I'm just...

Hello guys, Consider a partially filled tank with water where the acoustic field can be described by the Helmholtz equation. The boundary condition at the water surface would be \frac{∂p}{∂\vec{n}} = -j\rho_0\omega\frac{p}{Z} where Z is the impedance of the water surface. What would be...

Hello guys! I have to model the acouctic field within partially filled cavities. So consider a rectangular or cylindrical cavity that is partially filled with water. I would like to model the water layer as a sound absorbing wall by prescribing it as a surface impedance boundary condition...

Im trying to complete a worked example and just looking for validation whether what I am doing is correct. I am given the following: Supply: 230V ∠0° R: 100Ω ∠0° χL: j10Ω ∠90° χC: -j40Ω ∠-90° I struggled a bit with the j operator and using the polar/rectangular functions but this is what I've...

Hi, I'm in a bind trying to determine how to handle impedance matching through a joint of copper wire sandwiched between two 50-ohm coaxial cables (the joint is an interface between atmosphere and a UHV system). There is a signal pulse with a rise time of 2 ns coming through one of the coaxial...

I need to somehow take the output of a CMOS IC and transmit that signal over a 50 Ohm Microstrip line. The output impedance of the CMOS IC is about 15 megaohms. I see a lot of examples for going from 75 ohms to 50 ohms or similar but nothing on something of this magnitude. Any ideas? CMOS...

... sound wave? I need a simple method to calculate the impedance between water and silicone as ultrasound passes through them i.e. how much of the signal is reflected at the water silicone boundary. The problem is I am having trouble finding the required equations, Wiki is extremely...

The question is: The voltage source in the above circuit is a sinusoidal AC source with constant amplitude and constant phase shift but an adjustable frequency. Calculate the frequency ω at which the phasor current I...

Hey just to make sure, can we say apparent power S = V^2 / Z for a complex impedance Z? And do we have to worry about conjugates at all? Cheers

1 “earthing” for bonding of equipment and circuits to common plant earth electrode potential, 2 “protective earthing (PE)” when this bonding is required for personal safety provisions 3 “grounding” for interference suppressing bonding of screens, sys- tems with ground level 4. low-impedance...

Homework Statement Hello everyone, I have recently come under some stress from not being able to get these answers correct. I need to calculate these values: Zeq IT XL2 XL1 VR1 VR2 VL1 VL2 For this series circuit: And these values: Zeq IT XL2 XL1 IR1 IR2 IL1 IL2 For this parallel circuit...

I found a fast solenoid valve lying around (~1ms rise time) so I thought it would be fun to hook up to a compressed air line and use to generate some really loud bass. I hooked it up to a function generator and air supply only to find that it was disappointingly quiet (well not quiet, but...

Hi, I have been having this question for a long while. From Pozar's book (Microwave Engineering), on page 336, when he was solving for the resonance response and the Q factor for a Lamba/2 resonator terminated by an open circuit, and coupled to the feed line through a series capacitor, at some...

Homework Statement SOURCE: v(t) = (311)cos(314t) [v] IN SERIES WITH: R = (0.3) [Ω] L = j(0.7) [Ω] "load" = 2.5 + j(1.0) [Ω]Homework Equations Find the instantaneous current, and the phasor current. The Attempt at a Solution (1.) I first found the frequency of the source: (314) / (2*pi) ≈ 50...

Homework Statement The impedance of the circuit shown is: A. 41.1 Ω B. 100 Ω C. 173 Ω D. 187 Ω E. 241 Ω Homework Equations Z= sqrt (R^2 + [Xinduct - Xcapac]^2) Wd = 1/sqrt(L * C) Xinduct = WdL Xcapac = 1/WdCThe Attempt at a Solution I think my issues come with the 2nd to 4th...