Core Definition and 484 Threads

1. Homework Statement As shown above Homework Equations *Not too sure if they are relevant. Pretty sure there's more. We have textbooks from the library as references but we still can't quite figure it out :/ Φ = BcAc = BgAg B = Φ/Ac = (Ni/R)/Ac R = lc/(Ac.μ) The Attempt at a Solution...

From, http://www.bbc.com/news/science-environment-38372342 "Scientists say they have identified a remarkable new feature in Earth’s molten outer core. They describe it as a kind of "jet stream" - a fast-flowing river of liquid iron that is surging westwards under Alaska and Siberia. The...

Hi I am looking around for some way to model magnetic fields through a simple core with an air gap similar to this image : I was thinking Comsol... but Comsol is so hard to figure out, their documentation is terrible... I was looking at FEMM, but its only on windows. Does anyone know how to...

Homework Statement [/B] A single phase transformer circuit is assembled with an RC load. A voltmeter is connected to across the capacitor and an ammeter in series with the primary. The output of the ammeter is connected to the X-channel of an oscilloscope and the output of the voltmeter is...

In a transformer, let's say we have: I1, I2 - currents through the primary and secondary winding V1, V2 - voltages N1, N2 - number of turns F1, F2 - magnetic fluxes through core, produced by the currents I1 and I2 (they are opposing...) R - the reluctance of the core We have V1/V2 = N1/N2...

I'm currently in conceptual phase of designing a coil gun. Thinking back to my physics 2 class-- and some of my independent studies-- I understand an EMF produced by a solenoid with current through the wires of it is strengthened significantly by a ferrous core, as seen by the classic experiment...

I had a quick question regarding particles touching each other. I know no one can really say for sure but inside a black hole where the gravity is astronomical would the particles be considered to be pressed up against each other? are the forces involved enough to compress atoms down into the...

Homework Statement Low-mass stars like the Sun obey the core mass-luminosity relationship as they burn H in a shell and climb the RBG (Red Giant Branch). What is the energy released per unit mass when fusing hydrogen into helium? Homework Equations The core mass-luminosity relationship: $$...

Wikipedia says that solar core has 15 millions of Kelvins ( https://en.wikipedia.org/wiki/Solar_core ), what translates into ~1.4 keV energy per degree of freedom. For nuclear fusion we need to take the two nuclei to distance of range of nuclear forces: ~1fm (...

Hello friends, I am trying to find how calculate the magnetic field created by current loop considering that there is a some geometry of material that can enhance the magnetic field. I thought it can be solved by multipling by permeability μ but realized that the iron core changes the picture of...

Hello, I am wondering if anyone can help me with the following question. I want to find out how the size of the core in an inductor influences the current induced in the secondary coil, and whether a smaller core is more efficient if efficiency is defined as inducing the highest current in the...

Dear all, I would like to learn more about what happens to CRs during the reactor cycle. At the beginning of the cycle large excess reactivity is present in the core and has to be compensated with burnable absorbers (lumped in rods and WABA coating), chemical shim and CRs. There are several...

Hi I am someone researching vapor core reactors from a historical perspective. I have a technical question. In a congressional document I found it is stated that a vapor core reactor would have 35kW of power per square inch. Am I right in calculating that a cubic inch of a vapor core reactor...

I need help in calculating the magnetic field outside of an iron core solenoid at different distances. I have made an electromagnet by taking a 99.99% pure iron (5cm in length and 1 mm in radius) and wrapping wire over it. I have measured it's magnetic field at the end and cannot find an...

Hello. I am trying to design an EI-core electromagnet (think two c-shaped cores with their gaps abutting). The coils would go on the top and bottom legs of the E (legs B and C in my sketch). There is a sketchbelow and you can find one here...

The graph below shows the efficiency of an AIR CORE transformer at different voltages (from MAINS). At low voltages, it has high efficiency and gets lowers because of high magnetising current causing heat loss. But why is it higher at some points again? I do not understand this pattern. Please...

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...

Simple question, how far from the core does each layer of the sun's atmosphere start? I couldn't find enough information in google.

Few days ago I got sample of toroidal core from my friend. Technical details of core OD-10cm, ID-6cm, height- 5cm and wet about 1.845 kg(M4 grade CRGO). I want to make toroidal transformer using this core but how to calculate core area and maximum VA capacity of core. attach Test certificate of...

I had a bit of rattle about this here before but I hope you folks ain't fed up with me yet.:) So after some trial and error I've built a working smps for my amplifier , it's pretty high power ,when testing dummy loads i got up to 2KW , since I don't need more for my project I never went further...

i am a physicist now i am doing Ms in nuclear engineering ... i need to understand basic concepts ... neutron transport equation ? what is the transport phenomenon actually ? and pressure drop calculations in core ... please help thanks in advance

I have been studying astronomy and astrophysics for about 2 years now, though on my own time and by my self. A recent question came into my mind, Can arctic planets exist close to their star? Now, in my understanding of planetary science, in order for a planet to be cool and close to the sun, it...

If i have a transformer, and i need to calculate the core losses using this approximate equivalent circuit, according to the lectures ( taking an introduction to electrical machines course in college) the Pc ( power lost in core) = (V1)^2/Gc, but the professor clearly stated that the core losses...

Would it be possible to send a robotic probe to the Earth's core?

Hi everyone, I have lots of (potentially dumb) questions about this "project" I'm working on. It's a voice coil actuator, but with things a bit reversed. Here's how a regular voice-coil actuator is constructed: The rod that is inside the coil is a magnet and the outer cylinder continues the...

http://www.wired.com/2013/10/mars-polar-ice-sample-return-1977-1978/ I found this old Wired article interesting. It makes me wonder, with all the cash that is thrown at Mars exploration these days, why an updated version of this has not been attempted? It would seem that analysis of a Martian...

I have two systems that are approx. 300-400ft apart that I am connecting via a 10 Gig fiber connection. The fiber I am using is a 100um core MM fiber and the switches will be using a 50um core OM4 (4700 MHz*km) SFP module. Is there a way to find out what type of loss I should be expecting, is...

I'm not 100% sure if this question has been asked/answered or not but I was curious about this subject and I fear I'm not knowledgeable enough to figure out this question for myself. I know that the gravity at the surface of the sun is roughly 28g, but as gravity gets more intense the closer to...

Homework Statement We can make a rough estimate of how much the envelope of a red giant should expand as a result of the contraction of its core based on conservation of energy. We will consider a star of mass M and initial radius R, with a core of mass Mc and radius Rc. We will focus on the...

I'll answer this in this thread, later today.

Dear Guys, It will be really helpful if some one can give me the calculation step by step or some calculator where in I can resolve my long pending problem. Thanks in advance I will be really glad to have a correct answer. The Q is below Calculate temperature rise in 3 core cable after 3 hrs...

Hi, So say you have a magnetic flux in a closed magnetic path circuit (like a TX core). Well I mean we draw arrows and stuff to indicate how the magnetic flux travels, but after watching this: I'm having trouble understanding why there is any flux moving through at all. Can someone please help...

For research purposes, what would be the result of Electrical flow or magnetic strength if an Insulated copper Coil were wound around a pice of copper pipe?

Could neutron star jets with velocity greater than 0.9c be caused by a mix of ultra-relativistic core material escaping the star? See this link: http://www.dailygalaxy.com/my_weblog/2015/08/neutron-star-jets-near-speed-of-light-rival-those-of-black-holes.html

Hi. I use maxwell 3D eddy current solution type. i want to find out core loss. please help me.

Hydrogen electrons can spin-flip and emit a 21 cm photon. Can core electrons in a metal like lithium spin flip? If so, is the energy required to do so similar to hydrogen?

Hi everyone, I read somewhere that when a coil is wound on a magnetic core it's electrical length becomes longer than it's physical length. I remember seeing this formula L=l * sqrt Ue Where L= Electrical length l=actual (physical) length Ue=Core permeability Does anyone know if this is...

Has anyone considered the iron core of a transformer to act as a transmission line or waveguide, where it conveys energy from primary to secondary? The core seems to resemble a "magnetic version" of the single wire Goubau line.

Homework Statement Exercise: Hexachlorobenzene (C6Cl6) is a highly toxic waste product of pesticide manufacturing. It is resistant to biodegradation. Sediments at the bottom of a reservoir in the Upper Mississippi River catchment have been found to contain high C6Cl6 concentrations. The...

To begin with, I am an enthusiastic but very amateur physicist. I am working on my knowledge by taking online open courseware, buying textbooks and doing all the questions. I recently bought Astrophysics of Planet Formation which is no doubt out of my league but I like to pick at it from time to...

Homework Statement Iron core solenoid, with 50 turns per cm (5000 per metre) Current = 0.2A Measured B field = 1.58T Calculate: i) The applied field, Bapplied ii) The magnitude of magnetisation, M, of iron alloy Homework Equations For a long solenoid, Bapplied=μ0nI And, generally...

I've been googling around, and I can't seem to find a straight answer to this: Do eddy currents generated within an inductor core change the inductance, the impedance, or both? My reason for asking is to understand whether more or less eddy currents will change the resonant peak of the...

Hi, may I ask about this: In a normal orbiting system, if the orbiting object has the right velocity, it will stay in a stable orbit around the more massive one (to be precise, they will both orbit around their common center of mass, but for a galaxy this coincides with the galactic center)...

Hello folks, I'm looking for a way to measure core loss in RF transformers and inductors. I found a PhD thesis here: https://vtechworks.lib.vt.edu/bitstream/handle/10919/19296/Mu_M_D_2013.pdf which looks like just the ticket, but I'm having trouble understanding key parts. I've tried...

in my country colours of cable core are a)Single core RED b)Three Core RED-YELLOW-BLUE c)Four Core RED-YELLOW-BLUE-BLACK d)Five Core RED-YELLOW-BLUE-BLACK-GREEN. but can anyone tell me according to HD 308 S2 and IEC 60304 standard what should be the core colours of low frequency cables. ?

Can you please explain what the core problem of the information paradox is? Hi all! I've read many articles about it, watched videos, argued with some physicists, and yet I can't grasp at all where the paradox lies. For example, from the Wikipedia: "An important difference between the black...

The new curriculum schools are teaching now for math in elementary is Common core, which is a visual representation of addition, subtraction, multiplication etc... I've seen a couple videos, articles and stories of some, what i believe to be, outrageous accounts of unfairness towards the...

I've seen a lot of complaining on the internet by parents about the new way addition and multiplication is taught in American schools. I looked at it, and have to admit, at first, I thought it was insanely overcomplicated and worse than the way I was taught where you did one digit at a time and...

Hi all.. I am currently working on a project where i need to wound toroidal core halfway (not completely) so that part f the core is exposed. With that part, I need to lift weight a certain amount of weight (not fixed at this point). I am trying to understand what kind of equations would be...

Hi everyone. I've been seeing certain posts circulate around social media, claiming that math is now taught differently in school than it was before. Here is one such image: I'm not sure if this is true, or if it's just one of those "back in MY day" rants. Anyways, I'd like to see discussion...