Induction Definition and 999 Threads

The magnetic field that is oriented perpendicularly through a 9.2 cm diameter coil of wire drops from 6.4 T to 6.1 T in 0.076 seconds. What is the emf induced in the coil? Trying to answer this. My question is, if they are perpendicular then does that mean that cos90 makes phi = BAcos theta...

Hi , before I ask I want to say that I have done my “ homework” I did a search on this forums and I found a few hits but I couldn’t quite understand them or the numbers turned out wrong after I did my calculations. So I wanted to make a fresh thread , hope you folks will guide me , thanks. So I...

Hi all, This particular query is purely theoretical. Assume a standalone synchronous generator feeding power to a single induction machine (the only connected load) which is made to run as induction generator at super-synchronous speed. What will be the prevailing electrical conditions in such...

Hi All, I am glad to have found this site as it offers a great range of information. I have looked through similar threads before posting this and didn’t find anything that answered my questions. I am to build an induction heater(cooker type) using a half bridge series resonance circuit as a...

This is in reference to a POTW, http://mathhelpboards.com/potw-secondary-school-high-school-students-35/problem-week-135-october-27th-2014-a-12786.html. The logic behind this problem is simple, the number 2^{2^x} can only have factors of 2. But (n + 1)^3 - 1 contains an odd factor. Great...

Homework Statement The current in a solenoid (you may treat it as a long solenoid of length 2.0 m, turns, and radius 0.5 m) is decreasing at a rate of 1.7 A/s. What is the EMF at a point .35m inside the solenoid? Homework Equations B=N(mu_0*I)/(2a) where B=magnetic field, N=turns per...

Hope I can get some help here. I have a 1-1/2 hp. 115/230 volt single phase induction motor I want to use as a small generator. currently it's wired for 115 volt I need help with the math to calculate the proper capacitor/s to use. Running no load amps as a motor draws 18 amps. Name plate...

Stuff I'm wondering about: * can/does a conductors' cross-section influence inductive efficiency and/or directionality? * consider a 'wire' made from a dielectric material, with a conductive material evaporatively deposited on it's surface. if this wire were asymmetrical in section, e.g. it...

Ok so i got step (a) and found that $\int_{0}^{\infty} \,d (x^0)*e^(-ax)dx=1/a$ But i do not get how i should go about starting the next steps using the info from the first step(have not done a similar problem before so i need to get a grasp on the method)

Homework Statement [/B] Prove the following: (1x3x5x...x(2n-1))/(2x4x6x...x(2n)) <= 1/(2n+1)^.5Homework Equations none The Attempt at a Solution [/B] 1) Following the general steps of proof by induction, I first proved that the statement is true for the case n=1. 2) Next, I substituted n+1...

Hello! (Wave) I want to prove by induction, that the solution of the recurrence relation $T(n)=2T \left ( \frac{n}{2} \right )+n^2, n>1 \text{ and } T(1)=1$ is $n(2n-1)$. We have to suppose that $n=2^k, k \geq 0$, right? Do I have to prove the solution by induction with respect to $n$ or to...

Dear All, I am trying to understand this proof for using induction. Please help me! As per the book "Alan F beardon, Abstract algebra and geometry" The following... Quote: Proof: Let B be the set of positive integers that are not in A. Suppose that B = ∅; then, by the Well-Ordering Principle...

Hey everyone. This question revolves around induction/cap sealing - or just induction heating in general. Does anyone have an idea of why aluminum foil is used in induction sealing vs. using something that is magnetic, such as iron foil? My initial thought is simply aluminum foil being...

I have a new induction cooktop. I bought a pan rated for induction cooking for the stove and placed it over a burner while the stove was turned off. These pans tend to be rather heavy and the capacity of this pan was 3 qts. It had two handles, one was long and straight and the other was curved...

Hi everyone, I am trying to learn proof by induction method from http://en.m.wikibooks.org/wiki/Algebra/Proofs/Exercises And I have tried to solve the second problem attached with this post. It will be great if someone can tell me if I am wrong anywhere and then guide me. Thanks in advance.

Homework Statement a)Prove, by induction on n, that for all n ∈ N(natural numbers), Distance(x,y)<or equal to 0b)Prove, by induction on n, that for all n ∈ N(natural numbers), Distance(x,y)<or equal to n Homework Equations proof by induction: Base case P(1) then assume p(k) is true then...

Hello, I'm currently studying second quantization. I need to prove <n^\prime| n>=\delta_{n^\prime n} by mathematical induction in the number of particles representation. However I don't know how to do this proof having two natural numbers n and n^\prime. Must I prove it holds for <0|0>, <0|1>...

It just occurred to me that induction can be seen as a statement quite analogous to that of "a function whose derivative is 0 on an interval is constant on that interval". Suppose there is a property P about the natural numbers that we want to prove. Then let P: N -> {0, 1} be a function for...

Alright, I need to put my question in the context of the probably ubiquitous example of a conductor rod moving perpendicularly over a magnetic field to generate an emf between the two sides of the rod. That emf is equal to BLv (magnetic field, length, velocity) according to my book(studying for...

Homework Statement Consider the infinite series $$\frac{x}{e^x - 1} = A_o + A_1 x + \frac{A_2}{2!}x^2 + ... + \frac{A_n}{n!}x^n + ...$$ Determine that ##1 = A_o,\,\,\,\,\,0 = A_o/2! + A_1,\,\,\,\,\,0 = A_o/3! + A_1/2! + A_2/2!##. Show that for ##n > 1##, one can write the relations as $$(A+1)^n...

Homework Statement The sequence {xn} is given by the recurrence relation xn = cos(xn-1)sin(xn-2) for n ≥ 2 and x0=2 and x1=1,4. Show by induction that 0 ≤ xn ≤ 1 for all integers n ≥ 2. The Attempt at a Solution We formulate a statement: Pn: 0 ≤ xn = cos(xn-1)sin(xn-2) ≤ 1...

Do electrostatic fields induce charges on conductor surfaces faster than dielectrics respond to an identical field?

Hello, I need to prove the following: \sum_{i=0}^n\binom{n}{i} = 2^n by using something called mathematical induction. I understand, somewhat, what it is - we propose a statement and show that is true for n=1, then we assume that the statement is true for all n \in \mathbb{N}, which should also...

I'm a third year physics undergrad and I still massively struggle with electromagnetism - especially induction. Here's the opening part of the question: A loop is placed in an external alternating magnetic field that is perpendicular to the plane of the loop, with B=B0sin(ωt). Consider first...

I'm not sure if I'm posting in the right subforum because there is one about proofs, but it requires the question not to be homework-like, but I also need an explanation... Homework Statement Prove by mathematical induction: Let m be the smallest element of A\subseteq\mathbb{N}. If A...

I started graduate school this week after getting my BS in May of 2012. I'm having to review a lot of material. Heh. I've finished most of the homework, but I'm a bit stumped on two easy problems. The induction proof is no problem; I just haven't been able to find a formula. The nth partial...

Can you help me with this exercise? 1^{1}+2^{2}+3^{3}+4^{4}+...+n^{n} = n^{n+1} Thanks! PD. I was trying to solve, and i have this: 1^{1}=1^{1+1} = 1 = 1 a) k^{k+1} b) k+1^{k+1} = k+1^{(k+1)+1} a in b) k^{k+1} + k+1^{k+1} = k+1^{(k+1)+1}...

Hi guys I just want to know why changing magnetic flux in a coil induces emf? Thanks in advance.

Homework Statement Prove this by induction n ∑(1/√n) > 2(√(n+1) -1) i=1 The Attempt at a Solution I have tried for several hours, with no real progress. When i assume that it works for n=k, and then try to prove for n=k+1 i get 2(√(k+2)-1)... i don't know how to partition this...

I was just thinking about the "changing magnetic field through a loop induces an EMF" and thought of a conceptual question I'm having trouble with. So, imagine you have an open surface where there's a changing magnetic flux that you know (say its a plane of magnetic field coming toward you...

Watch this video: Permanent magnets moving relative to a stationary copper tube generate Eddy currents which result in Joule heating of the copper. Simple enough. Let's change the problem to a rotor with 4 (circumferential) permanent magnets rotating inside a stationary (aluminum or...

Homework Statement Find the error in the following proof that \all horses are the same color" 4. Claim: In any set of h horses, all horses are the same color. Proof: By induction on ##h##: Base Case: For ##h = 1##. In any set containing just one horse, all horses are clearly the same color...

Homework Statement Hi all, need a little help on an electrostatic induction problem. A positively charged metal rod is brought near to a neutral metal sphere. What is the charge of the metal sphere and the rod when the positively charged rod touches the neutral sphere. Homework Equations...

Hello, We had a short unit on mathematical induction, and I know my final exam will probably have one problem that says ''prove this relationship with mathematical induction''. I was wondering, is there some sort of step by step procedure to proving something using induction? Or is it...

$S_k>k^2$ $S_{k+1}:2^{k+1}>(k+1)^2$ $2*2^{k+1}>2(k+1)^2$ $2^{k+2}>2(k+1)^2$ Assume $x=k+1$ $\frac{2^{x+1}}{2}>x^2$ $2^{x+1}*2^{-1}>x^2$ $2^x>x^2$ right? $2^{k+1}>(k+1)^2$

$S_k:5\cdot 6 +5\cdot 6^2+5\cdot 6^3+ ...+5\cdot 6^k=6(6^k-1)$$S_k:5\cdot 6 +5\cdot 6^2+5\cdot 6^3+ ...+5\cdot 6^k+ 5\cdot 6^{k+1}=6(6^k-1)+5\cdot 6^{k+1}$ what do i do now? to prove $S_{k+1}$

Definition/Summary Mathematical Induction is a method of proving a series of mathematical statement labelled by natural numbers. This method usually involves two steps. First one proves the base case, then one shows that if the statement holds for some natural number, it holds for the...

Did i do this right? $2^n>n^2$, $n \ge 5$ $S_{k+1}: 2^{k+1}>k^2+2k+1$ $2^k>k^2$ $2(2^k)>2k^2$ $2^{k+1}>k^2+k^2$ And $k^2+k^2>k^2+2k+1$ RHS: $k^2+2k+1$ So $2^{k+1}>(k+1)^2$

I don't know what forum to post this under. PLEASE HELP ME THOUGH! Principle of Mathematical induction: Let $S_n$ be a statement concerning the positive integer n. Suppose that, $S_n$ is true. For any positive integer k, k $\le$ n, if $S_k$ is true, then $S_{k+1}$ is also true. Then $S_n$ is...

Hi all, I need your help with a Time constant question? I am studying for an exam via distance learning and don't feel they have covered this question, question taken from past paper. 2. A coil of inductance 2 H and unknown resistance is connected to a D.C. supply of 100 volts. After 4 ms the...

I was wondering if someone could show me the derivation of Faraday's Law of induction from the more fundamental Lorentz Force.

I want to design a single phase induction motor (1/3 HP,50Hz,220V). I face a problem to design the main dimension of stator and Slot shape and Rotor skew angle . Would you give some idea for design ? or any related book and software ?

Original Equation: 5+6+7+...+(n+4)=1/2n(n+9) Ok, I've tried everything to understand this. I'm just not getting it. I understand everything (n=1, k+1, etc) up until this point: "To continue with proof what must be done?". I know you must simplify the right side, but I don't understand how they...

Hi, I was wondering if there is a way to prove the area of the Koch Snowflake via induction? At the moment I have the equations: An+1=An+\frac{3√3}{16}(\frac{4}{9})n and An=\frac{2√3}{5}-\frac{3√3}{20}(\frac{4}{9})n These two don't seem to work together very well when trying to prove by...

Homework Statement Homework Equations The Attempt at a Solution Hello, I am working on the problem in the attached image regarding induction based on the inequality 2^n \geq n + 1 I am confused how to do this by proving that if it is assumed to be true for ## n = k ##, then how it is true...

Homework Statement prove by induction \sum_{j=1}^{n+1} j \cdot 2^j = n \cdot 2^{n+2}+2; n \ge 02. The attempt at a solution P(0) \sum_{j=1}^{0+1} j \cdot 2^j = 0 \cdot 2^{0+2}+2 2+2 here is where I need some help is P(k) \sum_{j=1}^{k+1} j \cdot 2^j = (k+1) \cdot 2^{k+3}+2 ?? then...

1^3+2^3+...+n^3 = \left[ \frac{n(n+1)}{2}\right]^2; n\ge 1 P(1) = 1^3 = \frac{8}{8} = 1 P(k) = 1^3+...+k^3 = \left[ \frac{k(k+1)}{2}\right]^2 (induction hypothesis) P(k+1) = 1^3+...+k^3+(k+1)^3 = \left[\frac{(k+1)(k+2)}{2}\right]^2 I start getting stuck here I foiled it out then let m =...

Hi, I'm really stuck on this assignment question and could do with a hand on the step by step process of how to get the answers. A three phase induction motor as 2 poles, a standstill voltage of 121 v/phase (Er), rotor resistance of 0.15Ω/phase (Rr) and a standstill rotor reactance of...

Hello! This is my second post about sequence reactances. This time- its in induction motor. To my understanding ( once again ) - In any network (symmetrical or unsymmetrical) , there would be 3 components- positive sequence component, negative sequence component and zero sequence...

$\newcommand{\uvec}[1]{\boldsymbol{\hat{\textbf{#1}}}}$ There is a uniform magnetic field $\mathbf{B}$ directed along the axis, and confined to a cylindrical volume of radius $R$. The magnitude of $\mathbf{B}$ is decreasing at a constant rate of $10$ mT/s. In unit-vector notation, what is the...