課程名稱︰材料科學導論
課程性質︰必修
課程教師︰郭博成
開課學院：工學院
開課系所︰材料系
考試日期（年月日）︰2008/6/17
考試時限（分鐘）：150分鐘
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
1.Why the magnetic moment of an atom in the magnetic material will oreien to
the applied magnetic field direction if the magnetic filed is large enough?
(10%)
2.Describe the change of domain configurations during magnetization for a
magnetic material.(10%)
3.Cite the major similarities and differences between ferromagnetic and ferrimagnetic
materials.(15%)
4.Cite the differences between type I and type II superconductors.(10%)
5.Explain why the resistivity of metal is increased woth temperature but the
resistivity of intrinsic semiconductor is decreased with increasing
temperature.(10%)
6.How does the electron structure of an isolated atom differ form that of a
solid material?(10%)
7.Some hypothetical metal is known to have an electrical resistivity of 4*10^-8
(Ω-m). Through a specimen of this mental that is 25mm thick is passed a
current of 30 A ; when a magnetic field of 0.75 tesla is simultaneously
imposed in a direction perpendicular to to that of the current, Hall voltage
of -1.26*10^-7 V is measured. Compute
(a) the electron mobility for this metal, and
(b) the number of free electrons per cubic meter. (10%)
8.Consider a parallel-plate capacitor having an area of 2500 mm^2 and aplate
separation of 2 mm, and with material of dielectric constant 4.0 positioned
between the plates.
(a)What is capacitance of this capacitor?
(b)Compute the electric field that must applied for a charge of 8.0*10^-9 C
to be stored on each plate (10%)
9.Briefly explain determines the characteristic color of (1) a metal and (2)
a transparent nonmetal. (15%)
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※ 編輯: billren 來自: 118.168.86.221 (06/17 19:51)