Core Definition and 484 Threads

Homework Statement I need to find the refractive indexes of the core and cladding of an optical fibre by using the specs found here http://www.photonics.byu.edu/FiberOpticConnectors.parts/images/smf28.pdf Then I'm suppose to calculate the Numerical aperture and compare it with the one listed...

Hi folks, I'm a Mech Eng who is trying his hand at some Electrical design so please forgive my ignorance. My set-up is as follows: I have a 3 phase source powering a 3 phase induction motor. If I then went half way along my power cable and put a separate current transformer on each of the...

When is a magnetic core considered "saturated"? At 50% of core - 100%? So I am doing some simulations of inductors on the Ansys Maxwell software for electromagnetic simulation. I have a simple inductor with a Metglas core and copper coil. I'm trying to figure out what current is required to...

I heard an interesting proposal - it sounds plausible but I'm here to see what you guys think. It is a way of explaining a diverse set of natural phenomena on Earth with one mechanism - rotation. The proposal is this: The core of the Earth rotates in the opposite direction to the Earth's...

If Earths core were larger taking up say 70% of its radius and the mantle were smaller. Would there be more or less plate tectonics?

Homework Statement When we have an iron core in a solenoid, the iron core will become magnetised. But if I were to put a piece of iron in front of the iron and solenoid the piece of iron will come out like in a door chime. But as it comes out, will the magnetic field be stretched and elongated...

http://phys.org/news/2012-08-nasa-mars-flight-explore-core.html Aww. Titan Mare Explorer looks way more exciting to me, even if we had results only when I'm 37 years old.

Homework Statement An iron core with a solenoid coiled around it is in a circuit with a switch and a dc current supply. In front of it, there is a iron ring tied to the ceiling such that it faces the solenoid without touching the circuit. When the switch is turned on what is observed and...

I have two coils standing next to each other. One is connected to a power supply and the other one is connected to a lamp. When I put an I-shaped iron core through both coils the lamp shines brighter than without the iron core. The same thing happens when I use a U-shaped iron core. When I...

(a) (i) Express \(\sqrt{48}\) in the form \(k\sqrt{3}\), where \(k\) is an integer. (1 mark) ...(ii) Simplify \(\displaystyle \frac{\sqrt{48}+2\sqrt{27}}{\sqrt{12}}\) giving your answer as an integer. (3 marks) (b) Express \(\displaystyle \frac{1-5\sqrt{5}}{3+\sqrt{5}}\) in the form...

1. The line \(AB\) has equation \(7x+3y=13\). (a) Find the gradient of \(AB\). (2 marks) (b) The point \(C\) has coordinates \((-1,3)\). (i) Find an equation of the line which passes through the point \(C\) and which is parallel to \(AB\). (2 marks)(ii) The point \(...

Homework Statement I am looking for a general explanation of when the total reluctance of a magnetic circuit is not equivalent to the sum of the reluctances if each area. In several examples the text has added 2 areas in parallel and then added the third area. I'm not 100% sure on when this is...

How big does a planet have to be in order for it to have a molten core or a magnetic field? Assuming no other large objects were close enough to affect the planet with their own pull or magnetic field. I would imagine the composition/density of the planet would play a factor as well, but do we...

Hi, I'm wondering if anyone has any sources for off-axis point calculation for multiple current carrying loops that contain a soft iron core. I have been using this resource so far and I can figure out how to include multiple loops. How would I approach these calculations with an iron core...

is there still single core cpus still in production?, before people start saying use multicore etc I've already explored this and the reason behind my unusual question is that I am trying to run an old game server on my pc, however it will not run on multi core systems the usual solution which i...

The Reference Frame: A confirmation of the 130 GeV dark matter-like bump - Lubos Motl [1204.2797] A Tentative Gamma-Ray Line from Dark Matter Annihilation at the Fermi Large Area Telescope - Christoph Weniger [1205.1045] Fermi 130 GeV gamma-ray excess and dark matter annihilation in...

in terms of what buying what is the dereference between hard and soft iron? i know an iron core is good but what about cast iron?

Scientifically, it doesn't make sense why you can't just wind up wire without really much air in the middle. In order to get more wire closer to the magnetic flux, why wouldn't you just wind up the coil tighter? I keep seeing ferromagnetic or air cores. Why not a tightly would wire so more...

Hello. I am wondering what are the properties of matter at the core of a neutron star. I read that it could be quark matter of strange matter, but overall uncertain. How can strange matter form if strange quarks decay very quickly into up quarks (the state of matter would last very shortly), and...

Homework Statement Calculate the typical energy of nuclei in solar core. Calculate thermal energy required for a proton to overcome the Coulomb barrier and get within range of strong nuclear force (10^-15m) Homework Equations None given The Attempt at a Solution I have the core...

Hello all, First time here and first time posting. Just like to say a quick hello before getting started... Due to the rise of solar PV panels being installed before the Feed in Tariff was cut earlier this year (in the UK) I've been thinking about the cable losses that these incur...

I have this solution that I don't quite understand d(ro*pi*D^3/6)/d(t)=-kr*Cao*pi*D^2 from here I would have thought to separate the variables and integrate but the solution says ro/2* d(D)/d(t) = -kr Cao I guess my question is how are you able to do that? If you take the derivative...

Homework Statement So originally Ag core notation should be -> Kr 5s1 4d10... but looking at it unchanged is -> Kr 5s2 4d9 Does that mean if i take an electron away I take away all the electrons from 5s2 and put them into the 4d8 shell and have Kr 4d10? Homework Equations The...

Homework Statement The AC power supply (maxium voltage 20.0V) in RCL circuit is run at resonance for the following parameters: R = 20.0 Ω L = 88.0 mH C = 79.9 μF When an iron core is added to the inductor, the self-inductance is doubled A) Find the frequency of the generator B)...

By a simple procedure , what should I do when I'm going through the thermal hydraulic design of nuclear reactor core...? .. I put initial guesses for the core dimensions ( fuel , clad , gap , length) initial guess for the fuel element pitch desired power ... I've found q'' critical heat flux...

I was recently going through electric machinery fundamentels by Stephen Chapman and noticed the graph of the core loss current. I need help in understanding the nature of the current graph plotted against time, like how its value stays constant for some fixed time then varies linearly.

Faraday's Law of Induction: EMF=-\frac{\partial \Phi}{\partial t} If two identical coil with same turns of wire and same dimension ( same cross section area in the middle), one has only air and the other has a magnet core. If the two placed in an uniform varying magnetic field, is there...

The inductor is initially an air cored one.When the Iron core is introduced,the resistance is found to increase considerably.Please explain.

Does anyone know of any electromagnetic core materials that either do not oxidize or who's magnetic and physical strength doesn't change much when it does oxidize? I need to make a room temperature electromagnet for hydrodynamic propulsion experiments. My first experiments used an air core but...

This article appeared March 2nd on Science Daily. Quite interesting. Any comments? http://www.sciencedaily.com/releases/2012/03/120302101413.htm

Let H be a subgroup of G and define the core of H as such core H={g\inG| g\inaHa^-1 for all a\inG}= \bigcap{aHa^-1|a\inG} Prove that the core of H is normal in G and core H\subsetH. I am having a hard time proving this because isn't the definition of core H basically saying the the core...

Homework Statement Ok, I need help, but it is for a project my son is working on. I am homeschooling him (13) and he is entered in a local science fair. He has designed an air core solenoid shock absorber for a bike. It more or less works, and we are working our way through the forces...

Hello everyone, I am trying to make a coil with the exact specs as the original. I have all the info I need except the actual core material used. I have all the measurements of the core and coil including: Wire gauge, # of turns and turns per layer,Bobbin dimensions, inductance without the...

Why is a "potential core" region of a jet called a "potential core"? We all know that there exists a region called "potential core" in a jet where there are no mean velocity gradients. My question is, why is it called a "potential" core?

Hello! I am a grade 12 student. If you are familar with the IB program, I am writing an extended essay (it's a 4000 word research essay) on how transformer losses are affected by temperature. Through two experiments I was able to determine how the losses of the primary and secondary windings...

Ok so this is kinda wishy washy but I don't know how else to explain this other than I feel like I am missing a critical piece of information as far as fundamental "math" goes. I am highly intelligent and and am a Mechanical Engineering Major who gets all A's, but I feel like I am missing a...

Hi There, What's the best core loading pattern optimization method? I believe this is very depended to experts knowledge, I mean the methods such as Genetic Algorithm or Neural Network or Ant Colony are not so useful for such these optimization. Please correct me if I'm wrong on this. Thanks

Was wondering how Jupiter's hydrogen liquid core converts the energy to create a magnetic field? and How exactly do these properties behave? I understand that my phrasing of the Question might be odd and may be wrong but i was just wondering how it worked

Anyone know where I can get a list of different core materials and their permeabilities?

I am working on a project and I need to find out what kind of core material this is... Unfortuantely I cannot ask the person who had it because they no longer have it. I don't think it's ferrite, the thickness is about .125", and the permeability is around 700-1000. It had several coils on...

does it follow that the larger the star the higher the core temperature? if so what would be the highest temperature attained. thanks

Hi all. I am shortly to begin work on my engineering FYP in automatic control and I'm hoping for some advice to point me in the right direction. The project will initially be an electromagnetic suspension rig (cylindrical winding with soft core suspending a permanent magnet below it via...

I am building a 400W power amplifier that is designed to work between 10MHz to 15MHz. I have a schematic that uses a set of isolation transformers and a set of step-up transformers. I ordered some powdered ferrite transformers from Magnetics (www.mag-inc.com). The isolation set is a...

please help me to solve this problem: Mars has a mean density less than the mean density of the Earth's mantle. How is it possible that Mars could have a metallic core given this fact? Hint: No calculations are required. Compare the densities used in part a) with the density of mantle rocks like...

I've recently been applying to colleges and looking at many of the universities dual core physics/engineering options, however, one of them also offer a "Pre-engineering" program. My question is simply: should I or should I not enter that program, or will the dual core physics/engineering option...

I am struggling with my mathematics indices homework. I think I have some correct answers so far but I'm pretty stumpted on some others. How would I go about solving the following equations. Homework Statement 1) 25 to the \frac{1}{2} - \frac{5 to the -4}{5 to the -5} Homework...

Please explain what is a CORE 2 DUO processor.

Homework Statement Calculate the radius of the Earth's core using the following data: Pe = 5,515 kg/m^3 (earth's average density) Pc = 11,000 kg/m^3 (core's density) Pm = 4,450 kg/m^3 (mantle-crust density) Re = 6377km (radius of the earth) Homework Equations im guessing we...

http://www.projectrho.com/rocket/enginelist.php#id--Gaseous_Core_Nuclear_Thermal_Rocket http://en.wikipedia.org/wiki/Gas_core_reactor_rocket How practical would this be? How much of a technological leap would be needed to achieve this? Would it make outer solar system missions possible...

I tried calculating the mass of the core of the sun but keep coming up with a number that exceeds the entire mass of the sun. I used http://en.wikipedia.org/wiki/Sun" facts on the sun. It says the core of the sun extends from its center to .2 to .25 times it's radius. I used the number .225 as...