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Callister - An introduction - 8th edition

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Questions and Problems • 835<br />

List of Symbols<br />

Symbol<br />

Meaning<br />

I<br />

Magnitude of current passing through a magnetic coil<br />

l<br />

Length of magnetic coil<br />

N Number of turns in a magnetic coil (Equation 20.1);<br />

number of atoms per unit volume (Equation 20.9)<br />

N¿<br />

Number of Bohr magnetons per unit cell<br />

m<br />

Permeability of a material<br />

m 0<br />

Permeability of a vacuum<br />

m Bohr magneton (9.27 10 24 Am 2 B<br />

)<br />

Important Terms and Concepts<br />

antiferromagnetism<br />

Bohr magneton<br />

coercivity<br />

Curie temperature<br />

diamagnetism<br />

domain<br />

ferrimagnetism<br />

ferrite (ceramic)<br />

ferromagnetism<br />

hard magnetic material<br />

hysteresis<br />

magnetic field strength<br />

magnetic flux density<br />

magnetic induction<br />

magnetic susceptibility<br />

magnetization<br />

paramagnetism<br />

permeability<br />

remanence<br />

saturation magnetization<br />

soft magnetic material<br />

superconductivity<br />

REFERENCES<br />

Bozorth, R. M., Ferromagnetism, Wiley-IEEE<br />

Press, New York/Piscataway, NJ, 1993.<br />

Brockman, F. G., “Magnetic Ceramics—A Review<br />

and Status Report,” American Ceramic Society<br />

Bulletin, Vol. 47, No. 2, February 1968,<br />

pp. 186–194.<br />

Craik, D. J., Magnetism: Principles and Applications,<br />

Wiley, New York, 2000.<br />

Jiles, D., Introduction to Magnetism and Magnetic<br />

Materials, 2nd <strong>edition</strong>, CRC Press, Boca Raton,<br />

FL, 1998.<br />

Morrish, A. H., The Physical Principles of Magnetism,<br />

Wiley-IEEE Press, New York/Piscataway,<br />

NJ, 2001.<br />

O’Handley, R. C., Modern Magnetic Materials:<br />

Principles and Applications, Wiley, New York,<br />

2000.<br />

Spaldin, N. A., Magnetic Materials: Fundamentals<br />

and Device Applications, Cambridge University<br />

Press, Cambridge, 2003.<br />

QUESTIONS AND PROBLEMS<br />

Basic Concepts<br />

20.1 A coil of wire 0.20 m long and having 200<br />

turns carries a current of 10 A.<br />

(a) What is the magnitude of the magnetic<br />

field strength H?<br />

(b) Compute the flux density B if the coil is<br />

in a vacuum.<br />

(c) Compute the flux density inside a bar of<br />

titanium that is positioned within the coil.<br />

The susceptibility for titanium is found in<br />

Table 20.2.<br />

(d) Compute the magnitude of the magnetization<br />

M.<br />

20.2 Demonstrate that the relative permeability<br />

and the magnetic susceptibility are related<br />

according to Equation 20.7.<br />

20.3 It is possible to express the magnetic susceptibility<br />

m in several different units. For

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