03/02/04
PROBLEMS Chapter 3.
3.1) Use the Lorentz force to describe how the angular frequency w changes for a
circular electron orbit (e.g. a classical Bohr orbit) in the xy plane when a magnetic field is
applied along the z axis.
3.2) Derive the expressi
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CHAPTER 1 PROBLEMS
1.1 What is the field in the middle and at the end of a 20 cm long solenoid (2 cm in
diameter) uniformly wound with 200 turns of wire carrying 0.5 amperes. Give fields B
and H in SI and cgs/emu units.
1.2 Consider the magnetic field i
3.45 Quiz, Spring 2004
April 8, 2004
3.45 Quiz, Spring 2004
I. M. Magnetician
NAME
April 8, 2004
(Answer questions on this sheet of paper)
1. a) Draw in briefly (1phrase) describe the direction of the magnetic field about the
infinitely long, current- car
Ch. 8 PROBLEMS
8.1. The figures below depict two orientations of domain walls in a uniaxial material.
Explain why each is unlikely.
8.2. Calculate the domain wall thickness and energy density for Co, Nd2Fe14B and
Ni80Fe20 from data in Ch. 6 assuming in ea
April, 2004
Chapter 10 Problem
1. Assume a 180o domain wall exists in a demagnetized, uniaxial magnetic material.
a) Sketch what happens to the domain magnetization and domain wall in
the two cases described below for H > 0 but less than saturation, i.e.
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April, 2004
Problems Ch 9
9.1. Solve for the magnetization vs. field for a) a thin film of amorphous iron boron
silicon (assume oMs = 1.6T and K = 0) with the field applied normal to the film surface.
b) a single crystal sphere of Ni with the field appl
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Problems Chapter 6
6.1 Show in Cartesian coordinates a) that 12 + 22 + 32 = 1 and b) that the
coefficient of K1 in Eq. 6.6 is given by 6.7.
6.2 Estimate the hard axis anisotropy energies of Fe and Ni from Eq. 6.1 and Fig. 6.1.
Compare your results with
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03/01/04
R.C. O'Handley 02/2004
2. MAGNETOSTATICS
Problems
2.1 Assume that an interface, similar to that sketched in Fig. 2.7 b but with m1 /10 =
m2 = m0 , is carrying a current (0, 0, J(y) = 2J0 (y/h + 1/2) and h is not necessarily small.
a) Sketch the
March 2004
PROBLEMS
5.1 Calculate the electron density needed to produce the first crossover in Fig. 5.21.
What would the charge density have to be for the first crossover to occur between the
second and third nearest neighbors of iron (aFe = 2.86).
5.2 D
March 2004
Chapter 4. PROBLEMS
4.1. Magnetic moments in ferrites.
a) Give the outer electron configurations and magnetic moments for the
following ions: Fe2+, Fe3+, Mn2+, and Zn2+
b) Using the site selection shown in Fig. 4.15, determine the preferred sit
Chapter 7 Problems and Solutions
March, 2004
PROBLEMS CHAPTER 7
7.1 Show that the magnetostriction constants of Fe and Ni are not of the sign you would
expect for dipole forces between atomic "bar" dipole magnets.
7.2 Consider a bar of iron with [110] alo
3.45
EXAM Solutions
April 5, 2000
1. (25 points) A long permanent magnet has a remanent induction of m0M r = 0.64T in the
y direction. Its cross section in the x-y plane is square
measuring a a and its length is very large in the z direction.
a) Sketch th