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    Flux & Flux Density

    Flux comes from the Latin word fluxus which means flow. There are two common uses for the term flux. In the transport phenomena, flux is defined as the rate of flow of a property per unit area. Flux as a mathematical concept also represents the surface integral of a vector field. Both definitions of flux are based heavily on mathematics and differential calculus.

    In the transport phenomena there are eight different types of transport fluxes. The eight include: momentum flux, heat flus, diffusion flux, volumetric flux, mass flux, radioactive flux, energy flus and particle flux. Each of these fluxes are vectors at each point in space and have a definite magnitude and direction. For incompressible flows, the divergence of the volume flux is zero.

    The surface integral of flux is


    F is the vector field

    dA is the vector area of the surface A

    The surface normal is directed usually by the right-hand rule. Once can consider the flux the more fundamental quantity and call the vector field the flux density. Often a vector field is frawn by curves following the flow. The magnitude of the vector field is then the line density. The flux through a surface is the number of lines. 

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    Solving a Diffusion Equation

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    X-Ray Tube Flux

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    China State in Flux

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    Gauss' Theorem

    If a vector field v is constant through space, use Gauss' divergence theorem to show that the flux integral ... must be zero, when taken over any closed surface S in three dimensions. Please see the attachment for the full problem.

    Charge on concentric grounded spheres

    Two conducting spheres are concentric, the inner sphere with radius a and the outer sphere with radius b. One sphere is grounded and the other is at potential V0. Find the charge on each when the grounded sphere is (a) the outer one and (b) the inner one.

    Calculation of total flux linkage of a coil

    ** Please see attachment for the complete problem description ** The formula is: Lambda=NxPhi=N1phi1+N2phi2+N3phi3...etc. 16. Find the total flux linkage of the coil shown in Fig. 47 (please see the attached file) if each flux line represents 2 * 10^-7 Wb. 1) 28 * 10^-7 Wb-turns 2) 33 * 10^-7 Wb-turns 3) 38 * 10^-7 Wb-

    Electric Field in a Tube

    What is the electric field due to a long hollow copper tube carrying charge with density 15 Micro Coulombs per meter, at a point outside the tube 3.6 cm from its central axis and not near either end of the tube? What is the field at a point inside the tube?

    Magnetic circuit model: A second winding is added

    The core illustrated in Fig. 13.51(a) is 1 cm thick. All legs are 1 cm wide, except for the right-hand side vertical leg, which is 0.5cm wide. You may neglect nonuniformities in the flux distribution caused by turning corners. a) Determine the magnetic circuit model of this device, and label the values of all reluctances in

    Magnetic field intensity at the centre of solenoid.

    Calculate the magnetic field intensity in ampere-turns per meter, for each of the following solenoids: a. I= 40 mA, N= 500 turns, I = 0.2m b. I = 100 mA, N=1000 turns, I=0.5m c. I = 60mA, N=600 turns, I= 0.25m d. I=10mA, N= 300 turns, I = 0.075m Iron coil has field intensity of 50 A*t/m, if the relative perme

    Rank surfaces in order of the electric flux through them

    Each of the surfaces listed below is a flat plate iwth area vector A that lies in a region of uniform electric field E. Rank the surfaces in order of the electric flux through them, from most positive to most negative. Surface 1 A= (5.0 m^2)i - (4.0 m^2)j E= (3.0 N/C)i - (4.0 N/C)j Surface 2 A= (5.0 m^2)i - (4.0 m^2)

    Magnitude of the magnetic flux through the top of a desk

    At a certain location, the Earth's magnetic field has a magnitude of 5.93E-5 T and points in a direction that is 70.0° below the horizontal. Calculate the magnitude of the magnetic flux through the top of a desk at this location that measures 109 cm by 60.0 cm. -Please explain and solve problem.

    Electrons per Atom and Bohr Magnetons

    The magnetization M of iron can contribute as much as 2 Tesla to B. If one electron contributes one Bohr magneton, how many electrons per atom on average can contribute to M? bohr magneton = 9.27 X 10^-24 J/T

    Flux Through a Surface Due to Earth's Magnetic Field

    At a certain location, the Earth's magnetic field has a magnitude of 5.93E-5 T and points in a direction that is 70.0° below the horizontal. Calculate the magnitude of the magnetic flux through the top of a desk at this location that measures 109 cm by 60.0 cm. Please explain and solve problem.

    Electromagnetics: Magnetic Flux and Induced EMF

    Which of the following statements are true about magnetic flux and induced EMF? 1) in order to make an induced EMF, the magnetic flux must be weak 2) in order to make an induced EMF, the magnetic flux must be static (steady) 3) the induced EMF has nothing to do with how fast the magnetic flux is changing through the

    exact value flux integral

    F ⃗=(18z+6y+cos^2 (x^2 )) i ⃗+(sin^2 (y)+5z) j ⃗+(e^(z^2 )+12y)k ⃗ Let C be the circle of radius 7 in the plane x + y + z = 24, centered at (8, 8, 8) and oriented counterclockwise when viewed from the origin. Find the exact value of c · d

    Flux Integral of Surface Plane

    Let S be the part of the surface z = 49 - (x2 + y2)2 above the xy-plane, oriented upward. Let D be the disk in the xy-plane given by x2 + y2 less than or equal to 7, oriented upward. F=yzi^+xzJ^+(-2+xy)k^ Compute the flux of F through D.' Compute the flux of F through S.

    Insulating material bombarded with electrons - charge density

    In pdf format, please provide the following, the derivations of formulae. I will draw all the sketches myself: When a block of insulating material such as Lucite is bombarded with electrons, the electrons penetrate into the material and remain trapped inside. In one particular instance a 0.1 microampere beam bombarded an

    Accrued Accounts Payable and VAT Taxes

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    Electrostatics: Charge density in a coaxial cable.

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    Flux of a Vector Field

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    Electrostatics: Electric flux through a rectangular sheet.

    A flat sheet is in the shape of a rectangle with sides of lengths 0.400 m and 0.600 m . The sheet is immersed in a uniform electric field of magnitude 74.5 N/C that is directed at 20 degrees from the plane of the sheet (see the attachment). Find the magnitude of the electric flux through the sheet.

    The outward flux

    See attached page for problem Let S be the surface of the solid hemisphere bounded by (see attached)

    Counterclockwise circulation and outward flux

    Use Green's Theorem to find the counterclockwise circulation and outward flux for the vector field F(x,y)= xyi + x^2j and the curve C, where C is the boundary of the region enclosed by the parabola y=x^2 and y=x