Generators Definition and 300 Threads

  1. I

    Generator load sharing

    I came across this statement in a generator manual I was reading(manufacturer Rolls Royce) The documentation barely touches any theoretical explanation as to how this works. I would like to ask specifically how this phenomena is achieved. If a generator's fuel output is increased, it produces...
  2. F

    Iterators and generators and the data they generate

    Hello, I have been focusing on iterators and generators and I understood a lot but still have some subtle questions... An iterator, which is a Python object with both the __iter__ and the __next__ methods, saves its current state. Applying the next() method to an iterator gives us one item of...
  3. S

    Looking for References on Single Phase Generators

    I am looking for a textbook or reference book that discusses single phase generators. All I can find are books that discuss three phase generators. Any suggestions?
  4. berkeman

    Small-scale hydropower generators installed in irrigation canals

    This is an interesting idea, with easier permitting and infrastructure advantages... https://www.cbsnews.com/sanfrancisco/news/hydro-power-generators-central-valley-irrigation-canals/
  5. E

    A Ballentine on construction of the (Galilean) symmetry generators

    In Problem 3.7, Ballentine says: The unitary operator ##U(v) = exp(iv·G)## describes the instantaneous ##(t = 0)## effect of a transformation to a frame of reference moving at the velocity ##v## with respect to the original reference frame. Its effects on the velocity and position operators are...
  6. abolfazlghasemi

    Hydrogen dew point in power generators

    Large power generators (for example 200 MW) are cooled by H2 in gas form. H2 temperature is +45 to +75 "C. So why hydrogen dew point is important in generator while the lowest hydrogen temperature is 45 "C? And in some Power Stations is monitored online... Thanks, a lot
  7. A

    I The different generators of canonical transformations

    Consider the phase space of a one degree of freedom mechanical system. We can pass from one phase space coordinates to another phase space coordinates via a canonical transformation. I want to focus on 1-parameter canonical transformations, $$(q_{0},p_{0})\rightarrow(q_{\lambda},p_{\lambda})$$...
  8. A

    I Spin, Angular Momentum, Momentum, Energy & NRQM

    Angular momentum is related to rotations. Momentum is related to spatial translations. Energy is related to temporal translations. Is spin related to anything? I only know the introduction to NRQM from Griffiths' book.
  9. J

    Help my understanding of DC generators please

    Hello, I am currently working on a engineering project for school and have been tasked with researching the basics of electrical theory. We are building a small, portable hydroelectric generator for the purposes of charging a cell phone or other small electrical devices. I already have the motor...
  10. platypi

    Computing the infinitesimal generators for the Mobius transformation

    I don't know where to start. I understand that the constraint ##ad-bc=1## gives us one less parameter since ##d=1+bc/a##. So we can rewrite our original function. I know how to compute the generators of matrix groups but in this case the generators will be functions. I also know there should be...
  11. R

    Why don't we use Direct-Charging Radioisotope Generators?

    when I was browsing wikipedia for some atomic battery information for my school project I found the thing called Direct-Charging Radioisotope Generator and when I tried to find more information about it I did not succeed. So I came here for some information about it or at least an answer why...
  12. K

    I Generators of Galois group of ## X^n - \theta ##

    As the summary says we have ## f(x) = x^n - \theta \in \mathbb{Q}[x] ##. We will call the pth primitive root ## \omega ## and we denote ##[\mathbb{Q}(\omega) : \mathbb{Q}] = j##. We want to show that the Galois group is generated by ##\sigma, \tau## such that $$ \sigma^j = \tau^p = 1...
  13. P

    Simple lie algebra that holds just four generators?

    I’m reading Weinberg’s QFT books, and stacking how to solve problem 15.4. Weinberg says there is no simple lie algebra with just four generators, but I have no idea how to approach this problem. If the number of generators are only one or two, it can easy to say there is not such a simple lie...
  14. berserkhealr

    Need help with Axial flux generator

    I am sure axial are used in wind turbines so i will use it as my example. Say you are using the wind turbine to generate power but its getting to windy and you want to slow down the turbine to bring it to a stop. What i want to know is ... If you can cut off the power that's been generated...
  15. I

    Why do wind turbines pitch their blades?

    Hi all. I'm new to this forum and to wind turbine technology in general, and I watched one of these one-minute videos explaining why wind turbines pitch their blades but it doesn not make sense to me. Why don't you just get a bigger generator? You'd get more energy for the same blades, same...
  16. nicholas_eng

    I Boost Generators: Physical Meaning & Observable Quantities

    So, all of the generators of the Poincare group are associated with pretty well-known physical quantities. Time translation is associated with energy, space translations with momentum, rotations with angular momentum, and boosts... well, boosts are generated by the "generators of boosts". Do...
  17. JD_PM

    Discussing the mathematical formalism of generators (Lorentz Group)

    I learned that the Lorentz group is the set of rotations and boosts that satisfy the Lorentz condition ##\Lambda^T g \Lambda = g## I recently learned that a representation is the embedding of the group element(s) in operators (usually being matrices). Examples of Lorentz transformations are...
  18. MathematicalPhysicist

    A How can the generators of ##U(1)## be traceless?

    In Peskin and Schroeder on page 681 they write: Now, as far as I can tell the generators of ##U(1)## are just exponents, i.e ##e^{2\pi ix}##, so how can they have a zero trace if it's just one number which never vanishes? Perhaps I am missing something here, can anyone clear this matter to...
  19. AutGuy98

    MHB Find n such that the group of the n-th roots of unity has exactly 6 generators

    Hey guys, Sorry that it's been a decent amount of time since my last posting on here. Just want to say upfront that I am extremely appreciative of all the support that you all have given me over my last three or four posts. Words cannot express it and I am more than grateful for it all. But, in...
  20. J

    Engineering Calculating Norton Equivalent Circuit for Complex Load Impedance

    V1 = 415cos(100πt) V2 = 415sin(100πt) Load Impedance = 50Ω (0.7 Pf Lag) = 35.002 + J35.705Ω Converting V1 & V2 to RMS values and V1 to a sin value: V1 = 415cos(100πt) V2 = 415cos(100πt-90) and from Asin(ωt+Φ) V1 = 415∠0V or 415 +J0V V2 = 415∠-90V or 0-j415 VIntially, i convert the the volage...
  21. Quix270

    Are there any DC generators without brushes and a commutator?

    Are any generator that produce dc current without brushes or commutator?
  22. P

    Chernobyl Alternative to generators to prevent the Chernobyl disaster

    The only material that I used to get this information is Wikipedia: https://en.wikipedia.org/wiki/Chernobyl_disaster#Steam_turbine_tests. I don't know if that's reliable enough...
  23. N

    Could Radioisotope Thermoelectric generators power electric cars?

    Could electric cars be given longer range by radioisotope thermoelectric generators like they use to power spacecraft in deep space?
  24. H

    Boosting a petrol generator with a car battery?

    Hi All, So i am looking to buy a petrol generator to run a 2.2KW electric motor. I was thinking of getting a 3KW model which under normal conditions this should be ok - but on start up I've been told an electrical motor draws 6 to 10 times the normal load, which is way too high for the...
  25. J

    Why don't electric motors use exciter coils like generators do?

    I remember (long ago, in college physics) learning about electric motors and generators, specifically about the "exciter" coils in generators which did a better job than permanent magnets, because of a sort of "turbo" or force-multiplier effect. I notice, however, that while basically ALL...
  26. H

    Generators of infinitesimal transforms from Goldstein (1965)

    This is a two part question. I will write out the second part tomorrow. I will be referring to pages 258-263 in Goldstein (1965) about infinitesimal transformations. Eqn 8-66 specifies that δu=ε[u,G], where u is a scalar function and G is the generator of the transform. How do I find the...
  27. T

    A Please help me clarify my misconception involving generators

    I am having a hard time understanding what it means for momentum to be the generator of finite translation. Why would a state |x'> translate to another state |x'+l>, and just stop after a distance l? Wouldn't the state want to keep translating due to the imparted momentum Px, in order to...
  28. karush

    MHB *elements and generators of U(14)

    elements and generators of U(14) \begin{align*}\displaystyle &\text{(a)the identity is } \color{red}{1} \\ &\text{(b) U(14) is the set } \color{red}{\{1,3,4,5,6,8,9,10,11,12,13\}}\\ &\text{(c) |1|}={\color{red}{1}} \text{ since }1.1 \equiv 12^1\\ &(d) |13|={\color{red}{2}} \text{ since...
  29. karush

    MHB What are the generators of $\Bbb{Z}_6, \Bbb{Z}_8,$ and $\Bbb{Z}_{20}$?

    nmh{707} $\textit{Find all generators of $\Bbb{Z}_6, \Bbb{Z}_8,$ and $\Bbb{Z}_{20}$}$ \begin707{align*} \Bbb{Z}_6&\quad=6, \textit{ all generators of } \Bbb{Z}_6 \textit{ are of the form } k\cdot1=k. where gcd(6,k)=1\\ &\quad \textit{ So } k=1,5 \textit{ and there are two generators of }...
  30. Mr Davis 97

    Showing normality by showing it holds for generators

    Homework Statement Let ##H = \langle S \rangle## be a subgroup of ##G = \langle T \rangle##. Prove that ##H## is normal in ##G## if and only if ##tst^{-1} \in H## for all ##s \in S## and ##t \in T \cup T^{-1}##. Here ##T^{-1}## denotes the set ##T^{-1}=\{t^{-1} \mid t\in T\}##. Homework...
  31. Mr Davis 97

    Proving that D_{2n} has generators s, rs

    Homework Statement Show that the subgroup of ##D_{2n}## generated by the set ##\{s, rs \}## is ##D_{2n}## itself. (i.e. show that ##\{s, rs\}## is another set of generators different than ##\{r,s\}##). Homework EquationsThe Attempt at a Solution It's not clear to me what exactly I need to do...
  32. Mr Davis 97

    Infinite cyclic group only has two generators

    Homework Statement Let ##H = \langle x \rangle##. Assume ##|x| = \infty##. Show that if ##H = \langle x^a \rangle## then ##a = \pm 1## Homework EquationsThe Attempt at a Solution Here is my attempt: Suppose that ##H = \langle x^a \rangle##. Then, for arbitrary ##b \in \mathbb{Z}##, ##x^b =...
  33. V

    Find monic generators of the ideals

    Homework Statement Let ##T## be the linear operator on ##F^4## represented in the standard basis by $$\begin{bmatrix}c & 0 & 0 & 0 \\ 1 & c & 0 & 0 \\ 0 & 1 & c &0 \\ 0 & 0 & 1 & c \end{bmatrix}.$$ Let ##W## be the null space of ##T-cI##. a) Prove that ##W## is the subspace spanned by...
  34. F

    Discrete logs and non generators

    Homework Statement This is just a question that i can't seem to answer while reviewing... Is discrete log well defined when the base is not a generator? Homework EquationsThe Attempt at a Solution For example, ##2^3 \equiv 2^6 (\operatorname{mod} 7)##. Taking the discrete log of both sides...
  35. N

    SU(3) Cartan Generators in Adjoint Representation

    I am trying to work out the weights of the adjoint representation of SU(3) by calculating the 2 Cartan generators as follows: I obtain the structure constants from λa and λ8 using: [λa,λb] = ifabcλc I get: f312 = 1 f321 = -1 f345 = 1/2 f354 = -1/2 f367 = -1/2 f376 = 1/2 f845 = √3/2 f854 =...
  36. S

    How does an Electric Bell use the Motor Effect?

    I need help in explaining how electric bell uses motor effect.
  37. tomdodd4598

    I Do the SU(n) generators represent any observables?

    Hey there, I've recently been trying to get my head around Yang-Mills gauge theory and was just wandering: do the Pauli matrices for su(2), Gell-Mann matrices for su(3), etc. represent any important observable quantities? After all, they are Hermitian operators and act on the doublets and...
  38. R

    What is the optimal RPM for charging a battery with an automotive alternator?

    Hello, I have a very basic question. And, admittedly, my knowledge is limited in this field. It is about the rpm of a rotor inside a generator. I know, to be aligned with the existing grid, standard frequency (of 50Hz, Europe and 60Hz, US) will require the RPM to be 3000 and 3600 respectively...
  39. N

    I Confused About Lorentz Generators

    I am looking at the generators of the Lorentz group. The literature commonly refers to the generators as Mij, Ji and Ki and defines: Ji = (1/2)∈ijkMjk I am confused about the factor of (1/2) in this equation as I thought that Mij is essentially the same as Ji This also shows up in Λ=...
  40. R

    Can waste CO2 be used to turn generators?

    If waste CO2 is collected through a pipe from a power plant can it be used to turn a generator by increasing its pressure with a funnel? See diagram: I have been wondering whether this is possible as I feel it could be very useful in the energy industry.
  41. J

    Do AC generators make use of interpoles?

    Hello, new member here. I'm giving myself a crash course and can't find a direct answer to my query outright, so here I am: Do A.C. generators make use of interpoles? I understand the concept of interpoles in D.C. machines, offsetting neutral plane shift; however, if we have, say, a brushless...
  42. lonelypancreas

    2 Synchronous Generators in parallel connection

    Homework Statement Two 3-phase 60-hertz 35-kilovolt synchronous generators (G1 and G2) each have synchronous reactances of j9 ohms per phase with negligible armature resistance. They are connected in parallel to supply a 36-megawatt load at rated voltage and power factor of 0.90 lagging...
  43. L

    I How many generators can a cyclic group have by definition?

    Hi, so I have just a small question about cyclic groups. Say I am trying to show that a group is cyclic. If I find that there is more than one element in that group that generates the whole group, is that fine? Essentially what I am asking is that can a cyclic group have more than one generator...
  44. A

    How exactly do motors and generators work by using magnetic fields?

    So I know if you move a charge in a magnetic field it induces voltage and hence a flow of charge is created which is current. ( Please correct me if I'm wrong). But that's pretty basic right. However, I'm having trouble understanding the use of split rings in the functioning of a motor. I would...
  45. I

    Vortex generators under your racecar question

    let's say you have a street legal racecar, flat front splitter with undertray going back to front tire stock undercarriage with crooked exhaust and couplings and then a badass rear difuser from the rear tire to the bumper. Let's keep this about "under the car" question. Vortex generators do some...
  46. S

    I SU(2) Generators: Understanding Lie Algebra

    Hello! I am reading some Lie Algebra and at a point the author says that for a vector with 3 cartesian components ##V_i## i =1,2,3 the commutation relations with the generators of rotation are: ##[J_i,V_j]=i\epsilon_{ijk}V_k##. Can someone explain this to me? I am confused as ##V_j## is a number...
  47. C

    B Why Negative Hydrogen/Deuterium Ion Generators?

    Auto-Search gives me some hints. I did a Google for "Hydrogen Ion Generator" and got a load of hits about "Negative Hydrogen Ion Generators". They almost seem to be 'fusion specific'. Are they used because the required end result is a neutral beam of Hydrogen/Deuterium for injection into the...
  48. G

    Eddy current losses in microelectric generators?

    For a microscale electric generator (where the driving force is a fraction of a Newton), can losses from eddy currents be significant enough to noticeably alter the rotational velocity of the rotor? Because my understanding is that the rotation is basically taken as a constant when examining the...
  49. hideelo

    A Srednicki's normalization choice for lie algebra generators

    IN Srednicki's QFT he seems to make two different choices for normalizing the generators of lie algebras. In chapter 24 (eqn 24.5) he chooses Tr (TaTb) = 2 δab and in chapter 69 (eqn 69.8) he chooses Tr (TaTb) = (1/2) δab Is there a reason for this? Is there any particular reason to make one...
  50. binbagsss

    String Theory-Virasoro Generators -- show commutator relation

    Homework Statement (I have dropped the hats on the ##\alpha_{n}^{u}## operators and ##L_{m}##) ##[\alpha_{n}^u, \alpha_m^v]=n\delta_{n+m}\eta^{uv}## ##L_m=\frac{1}{2}\sum\limits_{n=-\infty}^{\infty} : \alpha_{m-n}^u\alpha_{n}^v: \eta_{uv}-\delta_{m,0}## where : denotes normal-ordered. Show...
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