Induction Definition and 999 Threads

Hi i have few questions over here and need some expert/pro view with approaching the question. The proving one would be an issue to me as well. Hope people would be able to assist me here , because i am basically struggling with it :( thanks Questions : My Working : No idea how to...

Homework Statement A star-connected, three-phase synchronous induction motor takes a current of 10 amps from a 415 volt supply at unity power factor when supplying a steady load. If the synchronous reactance is 5 ohms/phase and the resistance is negligible, draw the phasor diagram and...

Homework Statement A farmer installs a private hydroelectric generator to provide power for equipment rated at 120 kW 240 V AC. The generator is connected to the equipment by two conductors which have a total resistance of 0.20 Ω. The system is shown schematically in Fig. 1. (a) The...

Hi... Need help understanding 1MW, 6kV, 1600 RPM,Cage Rotor Asynchronous Motor, 3 Phase, 4 Poles. I have the basic understanding of all ratings but have received very low price for this motor but when i searched on the internet it looked huge and had very high price as compared to what i have...

Homework Statement After you close the switch, There will be an induced current in the resistance R, Choose one of the following: Direction of current ... magnitude of current A to B ... decreasing A to B ... increasing B to A decreasing B to A... Increasing Homework Equations Faraday's law...

Homework Statement Prove by induction $$w_k = w_{k−2} + k$$, for all integers $$k \ge 3, w_1 = 1,w_2 = 2$$ has an explicit formula $$ w_n =\begin{cases} \frac{(n+1)^2}{4}, & \text{if $n$ is odd} \\ \frac n2(\frac n2 + 1), & \text{if $n$ is even} \end{cases}$$ Homework Equations The Attempt...

Hi All, I'm working on a process involving induction heating. I'm heating up an irregular shape ss die to make a bond. My dilemma is in my understanding of where the eddy currents will be that generate the heat (based on skin effect). The clam shell die is pictured below. The right hand...

Homework Statement Hi everybody! I am struggling with an old exam problem, could someone maybe help me out to figure it out? Here is how it goes: A rod with resistance ##R = 0.1 \Omega## lays over two parallel tracks (resistance ##\approx 0 \Omega##, ##l=10##cm). A battery is connected...

What exactly is happening to the electrons inside the wire while it is moving quickly downwards within the Magnetic field? Why do electrons move in one direction if the wire is being push down? I don't care what direction electrons move... I want to know WHY they move in one direction?

<--Why electrons move up if the Magnetic field is Horizontal? at 0:14 <-- the Magnetic field is Horizontal but the electrons are also moving horizontally...

Homework Statement [/B] Hi everyone, some school mates sugested id try this forum for help with this work i have :) - will try to keep it short We were trying to induce current in a coil and confirm the experimental results with math, but the math is way off and nobody is sure...

Homework Statement Homework Equations There are no equations here, only theoretical knowledge The Attempt at a Solution Hi, My approach was this: I know that with the positive charge on the sphere being lowered into the cup I will have the inner area of the cup have a negative charge and...

By reading on the internet I ve found various websites talking about the relation between gravitation and electromagnetism, and in particular, under: - "Small" Gravitational fields -"small" changes in energy with respect to time, The linearized enstein' s field equation becomes pretty much...

Homework Statement Prove by induction, that when r(r-1)(r+1) is an even integer when r=2,3,4... Homework Equations Prove by induction The Attempt at a Solution I began with the base case r=2, leading 6. Then I proceed with r=3, leading 24. Now if r=k is true, then k(k-1)(k+1) is also true...

If the axiom of induction was extended to include imaginary numbers, what effect would this have? The axiom of induction currently only applies to integers. If this axiom and/or the well ordering principle was extended to include imaginary numbers, would this cause any currently true statements...

How electricity passing through a conductor produces magnetic field around it. How an induction motor works. The energy or electricity which passes trough green earthing wire is transmitted into the ground. Why this energy is not conserved and can be used in future. All these three things are...

Hey I got a little imaginary experiment which is little bit confusing to me. Maybe somebody with knowledge in signal transmitting or just good knowledge of physics can help me out. So let's say there are two parallel conductors which length is endless and resistance is zero (no losses and...

For a standard solenoid, I've found that B=μnI where μ = permeability of the core (4π×10^-7 for free space) n = number of coils I = current Firstly, is the permeability of soft iron 0.08, as I found? Primarily, however, I'm wanting to know if this still applies for a mutual induction apparatus...

Needing a bit of help here. I am trying to transfer an AC signal to a straight conductor via induction. I am trying to quantify the difference in amount of transferred signal (amps) when the source of the signal is a small coil versus a parallel running straight conductor. I am thinking its...

Hi Everyone, I will try to keep this short as I can and to the point, there is a bit of a back story, so bear with me. For the last 18 months (on and off as life allows), I have been trying to develop an induction heating assisted machine for 2 reasons. 1 - To learn as much as I can by doing...

Since the field in the title is opposing the original magnetic flux that causes the induction, how can it be reduced? I understand that a laminated magnetic core can be used. 1) Where is this magnetic laminated core placed? 2) Can it be obtained from specialized manufacturers? 3) My choice for...

Homework Statement Consider the table: 1 = 0 + 1 2 + 3 + 4 = 1 + 8 5 + 6 + 7 + 8 + 9 = 8 + 27 10 + 11 + 12 + 13 + 14 + 15 + 16 = 27 + 64 Guess the general law suggested by these examples, express it in suitable mathematical notation, and prove it. Homework Equations [/B] It's clear that if...

Homework Statement [/B] Three conducting loops, all with the same resistance ##R## move towards a uniform and constant magnetic field, all with the same velocity ##v##. Their relative sizes can be identified by the grid. As the loops move into the magnetic field an induced current begins to...

Assuming you've sufficiently proven your inductive basis, can you complete a proof by induction in the following manner: Make the inductive hypothesis, assume P(n) is true for some n. Assume P(n+1) is not true. If it follows from the assumption that P(n+1) is false that P(n) must also...

Homework Statement When there is a changing magnetic flux, emf is induced in the solenoid. The solenoid is made up of circular loops of wire. My first question is, since emd is induced in the solenoid, is there a site of higher voltage and another site of lower voltage? My second question is...

Hi all, I have a 1 HP capacitor start motor (old, c.1950) that runs an air compressor in my little workshop. When it's running, the lights in the shop and the whole house dim and brighten rhythmically, at about 5 Hz. This, of course, is related to the compression cycles of the compressor, but...

Hi, I am interested in the basics of "goal ref technology", but I was not able to find a lot of material. Just one very brief wikipedia page and some paragraphs at the http://www.iis.fraunhofer.de/en/ff/kom/proj/goalref.html#. Does this work a bit like the anti shoplifting RFID tags? As far...

Homework Statement A three phase 220 V , 60 Hz, six poles 10 hp induction motor has the following circuit. Parameters on a per basis referred to the stator: Rs = 0.334 Ω, R’R = 0.147 Ω, Xs = 0.498 Ω X’R = 0.224 Ω , Xm = 12.6 Ω The rotational losses including the core losses amount to 262 W...

I'm trying to understand a 3 phase induction machine model used as a generator in a Doubly Fed Induction Generator (DFIG) arrangement in Simulink. In this model for the induction generator component, they have stated that the model is a "Positive sequence model" of the induction generator...

This is a graph for a magnet falling through a coil, it shows the p.d induced in the coil (the induced emf) when the magnet enters and then shows the induced emf in the coil when the magnet leaves. My question is why does the p.d appear to change direction? (i.e why the positive and negative...

Say you have a coil connected in a closed circuit. You then move a magnet inside of the coil and it remains stationary inside of the coil. Is the magnet, even though it is stationary, still inducing an emf in the coil or is it not? I'm guessing it doesn't induce an emf in the coil because...

In a 3-phase induction motor, rotor current demagnetizes the air gap and hence, stator draws more current (to keep the flux constant), which is the reflection of rotor current. This is like a rotating transformer which consumes active power. An induction generator on the other hand, supplies...

When does the rate of change of magnetic flux in linkage with a coil rotating in a uniform magnetic field equal zero?

Homework Statement Hello, I have this problem: Four long straight parallel wires are placed in vacuum according to the picture, the distance between each wire is a = 20 cm. Through each wire flows electric current I = 20 A in the specified direction. What is the size and direction of magnetic...

Suppose a 3-phase IM is operating on a 50Hz power supply. When the motor is loaded, more current is drawn from the stator because of the demagnetizing effect of the rotor current. But the rotor current has a lower frequency i.e. slip*stator frequency. Still the reflected current in the stator is...

Hi, I have a trivial question about electrodynamics. If you have a very long coil, a long solenoid. Keep the current constant and you will have no \vec{B} outside (magnetostatics). Let's write down the Maxwell equations: \begin{matrix} \nabla\cdot\vec{B} &= &0 \\ \nabla\times\vec{E} &=...

Guys, I have read Lenz's law and Faraday's law. My question is when the current is overall trying to keep the magnetic flux constant as that in initial time then if I permanently change the flux then why the current is not flowing through the conductor continuously to keep initial flux constant...

Trying to understand how a magnetic field induces an electric current Suppose you have a wire in the magnetic field like this: If you move the wire with a velocity of V to the left. Then the magnetic field should exert a force on the wire which ultimately on the charges in the wire. According...

Homework Statement Homework Equations I am not really good at this topic, but I think you would need both the right hand rules (one that involves finding direction of current via magnetic field as well as the one for finding magnetic force) The Attempt at a Solution So I drew out magnetic...

If you have: A Linear Induction Coilgun, basically like a series of Induction Furnaces, using copper coils with high AC current at a high frequency. Where the projectile traveling inside those coils has a shorted superconducting coil around the outside of it, embedded in the ceramic projectile...

Homework Statement Prove that 3^n>n^4 for all n in N , n>=8 Homework Equations The Attempt at a Solution Base case: 3^8>8^4 Inductive step Assume 3^n>n^4. Show 3^n+1>(n+1)^4 I tried a lot of approaches to get from the inductive hypothesis to what I want to show Ex: 3^n>n^4 3^n+1>3n^4...

The law states: So, what if the change is flux changes are proportionately equal parts of opposite polarities? Suppose you approach a coil with two magnets on either side of the coil, each set to repel each other's north or south faces; the flux increases, but in equal parts opposite polarity...

Hello, I have a light AC fan, that I wish to correct its power factor. According to my measurements, it has around 0.7 LAG power factor. Here are my digital measurements: Vsupply = 204VAC I(load) = 0.237Amps phi = 43 , pf = 0.7 LAG My target power factor (pf) is to be 0.85 , and to...

Hi Evgeny Thank you very much for your reply. I will try to be more clear this time and in detail. The reason why it was not as clear, as it's lengthy. I have the following $|{y}_{n}(x)|\le\int_{a}^{b} \,|k(x,s)| |{y}_{n-1}(s)| ds+\int_{a}^{x} \,|g(x,s)| |{y}_{n-1}(s)| ds$ , $x\in[a,b]$...

For the locked rotor test I have these values, P1 = 620W Stator line voltage = 32V Stator line current = 8.4A To calculate active power/phase, Po = (P1+P2)/3 But I don't have P2, Is P1 maybe equal to P2 ?

Hello is my proof be correct ? I wish to prove by induction that ${\psi}_{n}(x)\le F(n)$ , $x\in[a,b]$ ... (1) Let there exists a function $f(x,n)$ such that if ${\psi}_{n}(x)\le f(x,n) $ then ${\psi}_{n}(x) \le F(n)$ . I know that (1) is true for $n=1$ i.e. ${\psi}_{1}(x)\le...

I have read about Japan's solar power plant in space. Would it not be easier to build a plant similar to the huge circular spinning space stations you see in movies that create their own gravity/downward force? Once something that large is spinning in space could you not use the motion to...

Homework Statement I am attempting to create a generator using electromagnetic induction. I am using a push pull system to move a bar magnet through a coil to create current. But I am unsure of the dimensions to build it with and when I attempt to use the equation I get stuck. I am looking for...

Homework Statement Homework Equations no equations required 3. The Attempt at a Solution so here are my answers, can some please verify if these are correct. Thanks in advance :) a) i have no idea if I am labelling the poles correctly, or if the induced current is in the right direction ...

Homework Statement A uniform conducting ring of mass π kg and radius 1 m is kept on a smooth horizontal table. A uniform but time varying magnetic field ##\vec{B} = (\hat{i} + t^2\hat{j} ) T## is present in the region (where t is in sec and the positive y-axis is in vertically upward direction...