Induction Definition and 999 Threads

Here ##A=B_1\oplus B_2\oplus \cdots\oplus B_k## means that ##A## is block diagonal with ##B_i## along the diagonal. A proof that I've seen goes as follows. The ##k=2## case boils down to realizing that if ##v\in\beta_1\subseteq\mathsf W_1##, then ##\mathsf T(v)## is a linear combination of...

OK I've developed a workable grid tied "wind" inverter, Certified, installed and successfully operating waste flare gas utility grid connected net metering system, with its associated functional usable space heating appreciated with todays -40 degree wind chills. All this fully described...

If we by induction in the scientific method mean: "that the future will resemble the past" and The Problem of Induction states: "There is no logical necessity forcing nature to remain uniform" does The Problem of Induction implies violation of (global) conservation laws?

Hi everyone! I am trying to calculate the total power consumption of an induction heating setup, where ferromagnetic material is placed inside a conductive coil-formed solenoid, and alternating current is passed through the solenoid by a certain power supplier. My questions are: 1. Under such...

Goldbach's claim: every even natural number ##n>4## can be written as a sum of two prime numbers. Let's call this claim: G(n). Let's try to solve it by induction. For n=6=3+3, base check is correct. Suppose G(n) is correct and let's try to prove that it implies G(n+2) is correct as well...

Been stuck on this one for a while now. Base case is easy, n=1, we have x <=1/3, so trivially 1-x>= 2/3 and we are done. The issue is with the inductive step, I don't know how to use the hint, infact I am struggling to understand what is meant by the hint. Any help (or a full solution) would...

Please help me understand whether my understanding is correct. If I have a solenoid like coil with empty middle , and a magnet that goes through the coil, the coil is longer than the magnet, there is induction as the magnet approaches the coil until the moment when one of the magnet poles is...

For this problem, My solution is ##P(x) = a_nx^n + a_{n - 1}x^{n - 1} + \cdots + a_1x + a_0## where n is a member of the natural numbers Base case (n = 1): ##P(x) = a_0x^0 = a_0## Thus ##\lim_{x \to \infty} \frac{P(x)}{e^x} = \lim_{x \to \infty} \frac{a_0}{e^x} = a_0 \lim_{x \to \infty}...

TL;DR Summary: How to calculate induction heat flux (density) induced by an infinitely long wire in an infinitely large slab. Hi, I have to simulate induction heating caused by a straight long wire in a thick slab of material (no strict limitations). To make it, in the best case I should...

I want to measure tank circuit currents using *different* methods. Below is the tank circuit. The coupling transformer has 20 turns and has 10A @ 80khz going through it. This means there should be a maximum of 200A in the tank (20:1 turns ratio). I measure the voltage across the 2.6uF capacitor...

Some definitions: The following statement has been left as an exercise in transfinite induction in a handout. I'm looking at Wikipedia and am trying to follow their outline: 1. Show it for the base case, i.e. that ##\mathcal{F}_{0}\subset\mathcal{G}##. This is, however, trivial, since we...

Hello everyone, maybe some of you know the formula for the number of multiplications in the FFT algorithm. This is again given as ##N/2 \cdot log(N)##. Why is that so? Can you really "prove" this? I can only deduce this from what I know, because we have ##log(N)## levels and ##N/2##...

Two ideas: 1) Negative charged object get close to A then we close K1 key. So -10SI charge from sphere A moves to sphere B and 30SI charge moves from sphere B to sphere A. At this moment sphere A has 30SI charge and sphere B has -10SI charge. 2) We close K1 key so system of 2 spheres should have...

Hi, I'm having problems with the proof for the induction of the following problem: ##\sum\limits_{k=0}^{n} \frac{(-1)^k}{k+1} \binom{n}{k}=\frac{1}{n+1}## with ##n \in \mathbb{N}## I proceeded as follows: $$\sum\limits_{k=0}^{n+1} \frac{(-1)^k}{k+1} \binom{n+1}{k}=\frac{1}{n+2}$$...

Visualize a rectangular bare wire circuit with one side loose so that it can slide along the adjacent sides and thereby change the size of the circuit. There is a static magnetic field orthogonal to the plane of the circuit and linking the circuit. There will be a motional emf in the moving...

In Sadiku, he used the formula dλ=dΨ * Ienclosed/I to determine the total flux linkage for coaxial cable for ρ<a and for a<ρ<b, but I applied this formula for the solenoid and it didn't work, the way that works for the solenoid is by using λ=N*Ψ. So why we multiply by Ienclosed/I in the coaxial...

Hi, unfortunately, I am not sure if I have calculated the task correctly here Task a I have now proceeded in such a way that I thought that the magnetic field only flows through the area drawn in red. Which ##\frac{1}{4}## corresponds to the area of a circle. By the fact that the magnetic...

A changing current in a transformer primary produces a changing magnetic field, which induces a voltage in the secondary (correct?), but if no circuits are closed on the secondary, there's no current in the secondary (and therefore primary as well). So how is this voltage induced?

Hello all, I am currently studying for a physics a-level qualification in the UK, I use the AQA specification and I am having trouble understanding this image representing a scenario I found in my textbook. The first image in the three part diagram shows this rotating coil and to me, it makes...

There is a proof that shows by induction (and by contradiction) that the identity permutation decomposes into an even number of transpositions. The proof is presented in the first comment here...

Hi all, Looking to measure some magnetic waves being generated at an electric coil. Freq is between 0-20kHz and magnitude is pretty small <1T. Any have suggestions for the best tool to measure and log data of this magnetic waveform? Googling around, I found meters like this: [Possible spam...

I was wondering about the possibility of Induction heater powered by Bicycle Dynamo (alternator/generator) without using any other circuit element. Which means connecting 24 V 50 to 60 HZ AC to Coil with turns around 100 in pancake shape (10 inch diameter ) and Stainless steel plate of 3 mm...

If you have not built an induction heater yet it is a fun project. Build the small circuit with 6 yellow capacitors first. Induction heater is a fun project. I built a small induction heater then I wanted a more powerful one. A small unit is so simple you can build it in about 2 hours work...

I'd like to make an Induction Heater design for Cooking purpose, where heat can reach up to 400-500F or so. I read in some other forums, that it's possible. So I'm trying to get more ideas and possibly learn how this can be done safely (in case I make it / if it's really safe). The Idea is use...

As a transformer freq bet higher, inside induction get more efficient i.e. less loss: 1. Hysteresis loss = η * Bmax^n * f * V. 2. Eddy current loss( proportional to B2mf2Bm2f2 )Now it seems that losses increases with increase in efficiency... But the above equations are valid when max flux...

I had to repair (change bearings) on a single phase induction motor recently and I recalled an age old question I've had. What are the rotor end ring blades made for ? The only reasonable answer I can come up with is - they are for cooling of the stator winding ends that extend out of the...

My interest is solely on the highlighted part in red...hmmmmmmm :cool: taken a bit of my time to figure that out...but i got it. Looking for any other way of looking at it; I just realised that the next term would be given by; ##\dfrac{1}{4}(k+1)^2(k+2)^2-\dfrac{1}{4}k^2(k+1)^2##...

My take; ##\sum_{r=1}^n r(3r-1)=n^3+n^2## Let ##S_n=\sum_{r=1}^n r(3r-1)## and ##f(n)=n^3+n^2## then, ##S_1 = 2## and ##f(1)=2## hence the result is true when ##n=1## Assume that ## S_m = f(m)## for some integer ##m## then, ## S_{m+1}= (m+1)(3(m+1)-1) +S_m ## ## S_{m+1}=...

The Student's Manual simply applies l'Hospital's Rule n-times to arrive at ##\frac{e^x}{n!}\to\infty## as ##x\to\infty##. However, I'm wondering if I could use Mathematical Induction to prove this. Is the following correct and sufficiently rigorous (at least for an undergraduate-level Calculus...

TL;DR Summary: So I'm just confused when the question asks me to solve for the no load speed of DC motors and induction motors. Does no load condition mean that the output torque (Tout) is zero? This is what I was assuming so far for both DC and induction motor. Is no load condition the same...

I know I should use a limit $$B=\lim_{r\to l}{\frac{\mu}{4\pi}\cdot \frac{4rml}{{\left({r}^2-l^2\right)}^2}},$$,but in Wolfram I get a weird solution. https://www.wolframalpha.com/input?i2d=true&i=Limit[Divide[4rl,Power[\(40)Power[r,2]-Power[l,2]\(41),2]],r->l] What is the solution? It...

I'm trying to prove the statement ##n^2 + 1 < n!## for ##n \geq 4##. My proof by induction looks way too contrived. Is there a way to simplify it? Here's what I got. For n = 4, ##n^2 + 1 = 17 < 4!##. So, the statement is true for n = 4. Now let's assume it's true for n = k, that is, ##k^2 + 1 <...

(expression given to be proven) check for p(1)... 2=2 substitute (n+n) to And here is the problem, I just can't find a way to continue solving this problem

See the work below: I feel like it that I did it correctly. I feel like I skip a step in my induction. Please point any errors.

My first attempt was ##... + n^{2} + (n+1)^{2} > \frac {1}{3} n^{3} + (n+1)^{2}## then we must show that ##\frac {1}{3} n^{3} + (n+1)^{2} > \frac {1}{3} (n+1)^{3}## We evaluate both sides and see that the LHS is indeed bigger than RHS. However, this solution is inconsistent so I am asking for...

Consider a closed path consisting of a loop of wire with a nonconducting gap that completes the closed path. The wire is threaded through a toroidal permanent magnet, magnetized around the toroid (what I call a stealth magnet). The magnetic flux is considered to be confined to the magnet. The...

A standard textbook problem features a constant B field and a conducting loop that increases in area at constant rate. It is easy to work out the induced EMF and the associated electric field magnitude and direction (CW or CCW). The magnitude of the E field is E = B v where v is a velocity...

For calculating ##n_1## I had no problems as ##n_1 = 3##. PF: Show ##(1+x)^n > 1 + nx + nx^2 ## is true for all ##x \ge 3##. Let ##n = 3, (1+x)^3 > 3x^2 + 3x + 1 ## ##x^3 +3x^2 +3x + 3 > 3x^2 + 3x + 1 ## is true. Assume ## n = k ## such that ##(1+x)^k > 1+kx + kx^2, k \ge 3## is true. We...

Link to my insight Article it's right where I need you to start checking, read the above boxes to, check out the picture to see examples of the kind of sequence of sets we are dealing with. I need you to read the section jusr below the first picture entitled "3.0.2 Lemma 2.1: Nesting Property of...

Ok, would i be correct to approach it this way, Let ##n=1##. If ##n=1##, then ##5^1+3## is divisible by ##4##, the statement is true for ##n=1##. Assume its true for ##n=k## ∀ ##kε\mathbb{z}^{+}.## Then ##5^k+3## is divisible by ##4.## i.e ##5^k+3=4m## ∀ ##m ε\mathbb{z}^{+}## Let ##n=k+1.##...

In this video lecture (though I have linked the video at "current time", in case it doesn't; work please see the video at 19:16), the lecturer just works out (he is not explaining anything) the proof of Induction Principle starting from ##N##. Let me give out here what he did: Statement: Let N...

Proof: The proof is by induction. (1) When ## n=4 ##, the statement is ## p_{4}<p_{1}+p_{2}+\dotsb +p_{3} ##, which is true, because ## 7<10 ##. (2) Now assume ## n=k+1 ##. Then ## p_{k+1}<p_{1}+p_{2}+\dotsb +p_{k+1-1}\implies p_{k+1}<p_{1}+p_{2}+\dotsb +p_{k} ##. Thus ##...

Looking at how the induced EMF is proportional to the rate of change of magnetic flux, intuitively it seems that if I increase the velocity of the magnet through the solenoid, i.e. drop it from a higher height, the EMF should increase as well. However, I am unsure if this is true and can't seem...

The statements holds for the case ##n=1## \begin{align} 1+x \leq & 1+x+\frac{1}{2}\cdot 0\cdot x^2\\ =&1+x \end{align} Assume the statement holds true for ##n=k## $$(1+x)^k\geq 1+kx+\frac{k(k-1)}{2} x^2$$ Then, for ##n=k+1##, we have the following \begin{align} (1+x)^k\cdot (1+x)\geq&...

Imagine a magnet moving up and down so that its flux 'B' cuts the copper rod to produce an alternating emf, suppose if the movement is fast enough such that its frequency equals to the electron spin resonance frequency given by F = B x 2.8 Mhz per gauss, neglecting skin effect, more copper...

I have come to the conclusion that the sequence is 1 1 1 3 5 9... trying to do induktion and I get Tp+1=2^p+1, which means that 2^p +2p-1 + 2p-2 <=2^p+1 and this is not really solvable in any satisfactory way. What am I doing wrong?

Hi, Please find attached below the Induction Generator circuit. I have the following parameters: Parameter Value Rs = Rr (Resistance on stator and rotor) 0.2 Ω Ls = Lr (inductance on stator and rotor) 5 mH = 0.005 H p (number of pairs of poles) 2 f (frequency) 60 Hz Vsl (stator line...

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)...