State the meaning of permeability, write down the expression for the permeability of free space, and indciate how it was developed from the Biot-Savart Law.

Draw the B-H characteristic for:
a) a ferromagnetic material
b) a non-ferromagnetic material
and show how the permeability may be calculated from them.

Solution Preview

Please see the attached file.

SOLUTION

Before we discuss permeability, let us discuss the terms magnetic intensity (or magnetizing force) H and Magnetic induction (or magnetic flux density) B.

Magnetic intensity

It is the measure of the strength or intensity of the source (usually the current) that is causing the magnetic field. For example, when a current I is passed through a solenoid having n turns per meter, a magnetic field is produced with in the solenoid. This magnetic field is directly proportional to n and the magnitude of current I. Therefore, the product nI determines the magnitude of the magnetic field produced within the solenoid. Hence, for a solenoid, magnetic field strength H=nI.

Unit of H is Amperes/meter (A/m).

Magnetic induction

While magnetic intensity is the cause, magnetic induction is the effect. Thus, magnetic induction is the measure of the magnetic flux created by the magnetic intensity in a region. If the region is vacuum, the magnetic intensity H (cause) and the magnetic flux density B (effect) are related linearly.

Thus, for vacuum, B is directly proportional to H or B = μ0H where μ0 is the constant of proportionality known as the permeability of vacuum.

μ0 = B/H ...

Solution Summary

Magnetic intensity, magnetic induction, permeability etc. are explained in details.

I can see that a Darcy's law permeability equation exists and is as follows:
k = (volume of liquid x length of specimen)/(time of flow x cross-sectional area of specimen x deltaP)
In this equation, there are 2 parameters that I do not understand
1) When the equation refers to the "time of flow" (t) what is meant by that?

1) Would the passive movements of substances occur if the interstitial solute concentration was the same as the filtrate solute concentration?
2) Matching:
1.) Causes production of dilute urine
2.) results in increased sodium loss.
3.) Causes the body to retain more Potassium.
4.) Will cause water retention due to sodiu

During an experiment a neuropsychologist measures the membrane potential of a squid giant axon in the presence of a bathing solution of known composition. He then removes the cytoplasm and replaces it with a synthetic solution. At the same time he alters the external medium from that used before and again measures the membrane

Please submit in the excel document.
1. The owner of a computer store rents printers to some of her preferred customers. She is interested in arriving at a forecast of rentals so that she can order the correct quantities of supplies that go with the printers. The data is shown blow.
a. Prepare a forecast for weeks 4 - 10

Could you please assist with the problem attached? Thank you.
Maxwell's equations for a homogeneous, isotropic, uncharged medium of conductivity, relative permittivity, and relative permeability lead to the expression: (see attachment)
where E is the electric field. A linearly polarized plane wave of angular frequency w i

A long solenoid of length 8m with a cross-sectional area of 5.0x10^-5 m^2 contains 52,000 turns.
1) Find the self-inductance of the solenoid, assuming that the core is air.
2) If the current in the winding starts at 0 A and is increased steadily to 1.5 A in a time of 0.20 sec, what is the EMF induced in the solenoid?

An air-core solenoid with 63 turns is 8.00 cm long and has a diameter of 1.20 cm. How much energy is stored in its magnetic field when it carries a current of 0.780 A? (answer in µJ)

A coil of 500 turns is wound on a wooden ring having a mean diameter of 8 cm and a cross sectional area of 1.5 cm^2. Assuming relative permeability of wood is 1, calculate the self-inductance of the coil and the emf induced in it when the direction of a DC current of 5A flowing in it is reversed in 0.2 sec?