Flux Definition and 1000 Threads

Homework Statement The Earth possesses an electric field of (average) magnitude 150 N/C near its surface. The field points radially inward. Calculate the net electric flux outward through a spherical surface surrounding, and just beyond, the Earth's surface. Homework Equations Flux =...

Why does electric flux have 'cos θ' in its formula??

My textbook says "the net flux is zero through a closed surface that does not contain any net charge," and justifies it by saying that everything flowing in has an equal thing flowing out. This makes ABSOLUTELY NO sense to me.

This is example 27.2 in my textbook. I have the answer, but it doesn't make sense to me. I understand that if electric field is tangent to the surface at all points than flux is zero. Why, though, does my textbook assume that the ends of the cylinder don't have field lines extending upwards and...

So basically I was wondering whether it's possible to get the expression of ideal gas using molecular flux equation which is ##\phi = \frac{1}{4}\bar{v}n##. The derivation should be straightforward. I need to get the expression of pressure. Because the flux by definition already gives the rate...

Looking for any life expectancy data for water soluble flux going low Z. How long it takes for conductive material to migrate and cause low impedance bridges at any humidity or temperature.

Homework Statement I am just a little bit confused. I have a question that is asking me to explain what the physical significance of volumetric flux is. Homework Equations I am not sure that this problem requires any equations! The Attempt at a Solution I know that the flux corresponds to...

Homework Statement I was given this question. The wall of a building is constructed of face brick (10cm thick) and concrete block (50 cm thick) with an air filled cavity (5cm thick). The interior and exterior convection coefficients are 8.3 W.m^-2.K^_1 and 35W.m^-2.K^_1 respectively. The...

Homework Statement Calculate the outward flux of F = 3z\mathbf{e_{\rho}} + cos(\phi)\mathbf{e_{\phi}} + 2z\mathbf{e_{z}} through the base of a cylinder centered at the origin with radius \mathrm{R} and height \mathrm{2H}. Homework EquationsThe Attempt at a Solution I am unsure of how to tell...

So I was reading about magnetic semiconductors and I got confused so can you please clarify I will ask a question that is made up of two parts. Magnetic semiconductors are ... a) devices that alter or switch on/off electric current flow depending on the magnetic field strength etc applied OR b)...

For diamagnetic materials, when an external magnetic field is applied, the electrons having orbital magnetic moment in opposite directions spped up. how does this happen? The direction of magnetic momwnt is given by right hand thum rule. If there is an electron revolving in anticlockwise...

So far I have only found the initial papers of Deaver, Bascom; Fairbank, William and of Doll, R.; Näbauer, M. Is there any later and refined similar experiment result?

Homework Statement A long cylinder of radius a with magnetization vector M=M_0*(r/a)^2*a_φ. Find the magnetic flux density inside and outside the cylinder. Homework Equations J_m=∇×M J_ms=M×a_n[/B] A=(μ_0/4*π)*(∫(J_m/R)dv+∫(J_ms/R)ds) B=∇×A The Attempt at a Solution Basicly what I thought...

Homework Statement An uncharged nonconductive hollow sphere of radius 12.0 cm surrounds a 11.0 µC charge located at the origin of a cartesian coordinate system. A drill with a radius of 1.00 mm is aligned along the z axis, and a hole is drilled in the sphere. Calculate the electric flux through...

I was reading that the ITER will take advantage of the energetic neutron flux by using them and lithium 6 to breed tritium for more fuel, and to use multiple heat exchangers to grab their energy. And just to make sure that I'm reading it right, the main problem with the neutrons will be their...

What is the solution of heat transfer equation when there is continuous heating ( flux of energy) to one end of a metal rod? what will be the temperature profile before reaching the steady state? when I try the boundary condition where one end (x=0) is kept at T1, I got the general solution of...

Homework Statement I have uploaded a file that shows the question.[/B]Homework Equations I believe the only relevant equation is: flux = Q(enclosed)/E(knot)[/B]The Attempt at a Solution Well I have some questions first. The problem statement says that the sphere on the left has a net...

Homework Statement 6 Gaussian cubes are shown below. The surfaces are located within space containing non-uniform electric fields. The electric fields are produced by charge distributions located outside the cubes (no charges in the cubes). Given for each case is the side length for the cube...

Homework Statement The drawing shows an edge-on view of two planar surfaces that intersect and are mutually perpendicular. Surface (1) has an area of 2.20 m², while surface (2) has an area of 3.90 m². The electric field in the drawing is uniform and has a magnitude of 200 N/C. Find the...

We know Total Magnetic Flux B = B_0 + B_m Where, B_0 is the external field and B_m is the field inside a material. Now, we get, B = B_0 + μ_0*M (M is the magnetization) My question is - Do I always have to use μ_0 ? If yes then Why? The material isn't free space, is it?& also B =...

Homework Statement If the electric field is constant in direction (horizontal in the x direction) but its magnitude decreases from E1 to E2, determine the flux through a cubical box of side length L if four of the sides of the box are parallel to the field. Homework Equations ∫EdA = flux The...

Homework Statement Using Cylindrical coordinates, find the total flux through the surface of the ellipsoid defined by x2 + y2 + ¼z2 = 1 due to an electric field E = xx + yy + zz (bold denoting vectors | x,y,z being the unit vectors) Calculate ∇⋅E and then confirm the Gauss's Law Homework...

So if you have a single inductor then I assume that there is no flux linkage and that L = flux*N / i = L11 and so that flux is total leakage flux. If you have two inductors then the flux leakage is any flux that isn't flux linkage (the self flux is flux leakage). (flux21 is the flux in 2 from...

Homework Statement I have a coordinate system, (x,y,z). There is a uniform-magnetic-field of 2.0 T that exists along the direction of the y-axis. There is a rectangular plane bounded by the points (3,0,0),(0,1,0),(0,1,1),(3,0,1). Calculate how much flux is traveling through the rectangular...

Homework Statement I was asked to 'Use a very simple model to find how the Earth’s temperature should vary with latitude.' Homework EquationsThe Attempt at a Solution I was thinking about flux and how this should be proportional to the temperature. So I first thought about the area that is...

Faradays law tells us that a change in flux induces an emf. Now consider the phenomenon of motional emf. It is observed across the ends of an open conductor (ie one which is not in a circuit). It is always discussed in connection to faradays law. Where is the change in flux in the case of a...

I found two ways to solve this problem, but I get two different solutions, it's confusing because I can't see the flaw in wrong solution. 1. Homework Statement Long cylindrical inductor of diameter D1 and inductance L1 is connected to battery and creates magnetic field B1. Inductor is then...

Homework Statement Assume I want to calculate the electric flux through a spherical surface centred at point P with radius R which contains a point charge Q, that is not concentric with the spherical surface. Here, I can no longer assume that ∫∫sEdA = E.A, and I have to calculate the value of...

when we calculate the neutron flux in finite medium using sn method for steady state neutron transport equation, it gives us some numbers up to 1. I am sure its not the real flux, can someone explain how we can calculte the real flux using sn method.

can someone tell me , why must the magnetic flux be taken into account instead of magnetic field ?? thanks...

Hi, It's been a while but from what I remember when you short circuit a transformer, electrically it's like you've series'd up the coils and shorted the magnetisation branch. And when you open circuit a side of the TX it is like the current flows through a side then through the magnetisation...

I have a little problem about Stellar Flux. I've searched google and bing for info but to no avail. Please help me understand Stellar Flux. Thanks, Epicall Rounder

Gauss's Law states that if a Gaussian Surface encloses a charge ##q_{enc}## then the electric flux through the Gaussian Surface is given by ##\phi=q_{enc}/\varepsilon_{o}## . It also states that any external field does not contribute to the Electric Flux through the Gaussian Surface. I am bit...

Homework Statement Two threads, both having linear density μ1 and μ2 are connected and tensed with tension T. a) If traveling wave enters onto their junction, find ratios of amplitudes of reflected and input wave, transmitted and input wave, for μ2/μ1= 0, 1/4, 1, 4 and infinity b) Show that...

Hey there... As far as I know, electric flux is a scalar quantity which means that negative values are smaller than zero. This concept really confuses me since most of the exercises I dealt with suggest that negative flux somehow is larger than zero flux Example 1 the uniform field is directed...

to calculate emf i can use the flux rule -d(magnetic flux)/dt or the lorentz force line integral across the circuit. Is there a gudeline to follow for knowing when to use either (or both) of these methods? Thanks :D

Homework Statement A circular coil of diameter 24 mm has 40 turns. The coil is placed in a uniform magnetic field of flux density 85 mT with its plane perpendicular to the field lines. a) i Calculate the area of the coil ii The flux linkage through the coil. b) The coil was reversed in a...

Why is the electric flux defined as (electric field) x (area), Φ = EA? How do you come up with that equation? Is it because the electric flux is proportional to the charge and surface area?

Homework Statement A gas mixture contains 50% He and 50% O2 by volume at 500 K and 1 bar. The absolute mass fluxes of each species along the transportation direction z are ##\hat J_{He} = -0.8 \frac {kg}{m^{2} s}## and ##\hat J_{O_{2}} = 0.8 \frac {kg}{m^{2} s}##. Determine the mass and molar...

Homework Statement [/B] Find the outward flux of the vector field ## \vec F = y^2e^{z^2+y^2} i + x^2 e^{z^2+x^2} j + z^2 e^{x^2+y^2} k## across that part of the ellipsoid $$ x^2 + y^2 + 4z^2 = 8$$ which lies in the region ##0 ≤ z ≤ 1## (Note: The two “horizontal discs” at the top and bottom are...

Homework Statement Now, ignore the lengths given in the photo. Height (y) = .640 meters Length (z) = 1.18 meters Base (x) = .320 meters Magnetic Field (B) = 3.5 Teslas in the +X direction Homework Equations The problem is to find the magnetic flux through the surface of the...

Hi guys, I've seen a lot of textbooks converting between 2 apparent magnitudes to the ratio of 2 fluxes. But I just want to know how to convert 1 ( ONE, UNO , 1, NOT 2 ) flux to 1 ( ONE, UNO, 1, NOT 2 ) 1 Apparent Magnitude. I think I saw my professor wrote this down, but am not sure . Is this...

Hi to all of you, As the Biot-Savart-Law is based on experimentations in air, i like to know how to calculate the magnetic flux density in material with much greater permeability, where the circular like shape of the field distribution troughout the vicinity does not apply. Does anyone has a...

Hi all, Just a quick question about control of axial flux synchronous machine. Does it follow more or less the same technique ( which include PWM, inverter and dq transformation )? Is there any major difference from control of radial flux machine? Thanks in advance. Regards.

Homework Statement A bar magnet is held above the center of a wire loop lying in the horizontal plane, as shown in the figure below. The south end of the magnet is toward the loop. After the magnet is dropped, what is true of the current in the resistor as viewed from above? (Select all that...

I read in class 10. I am having problem understanding magnetic fields, magnetic flux,magnetic flux density,magnetic field strength,magnetic permeability and strength of magnetic field produced due to a straight and closed loop current carrying conductor at a certain point at a certain distance...

I know that the equation for magnetic flux is \Phi=\int \vec{B} \cdot dA. It seems to me that this is like integrating the density function a rod with respect to x, which simply gives you the mass which is constant. I was wondering whether the same thing applies here: is magnetic flux a constant?

Taken from wikipedia, "If several turns of the wire are made, this becomes where N is the number of turns..." when speaking in terms of flux linkage and coils of a wire. However, in terms of a straight conductor (e.g. transmission lines), flux linkage for a meter long straight conductor has...

Homework Statement I need to create an equation that can tell me the electric flux through the surface of a sphere (centered at the origin) due to a point charge placed at various locations in/around the sphere. For example, find the electric flux through the sphere (of radius = 1) with a point...

Homework Statement A 1x1x1 cm box with edges aligned in the xyz-axes is in the electric field E = (350x + 150)i N/C, where x is in meters. What is the net electric flux through the box? Homework Equations flux = ExAx + EyAy + EzAz The Attempt at a Solution I substituted into the formula...