A Best Way To Crack Gorenment Job Exams

Electrical Engineering Objective Questions { Material And Components }

113. In the four point probe method of determining resistivity
A. one probe point must inject minority carriers
B. current flow in only a small area of the sample
C. current source is connected to the two inner probes
D. the sample must be extrinsic

114.  A requirement of four point probe method of determining resistivity is
A. the current must be low
B. the current must be high
C. cross-section along the sample must be constant
D. current source is connected to two inner probes

115. Merit of four point probe method of determining resistivity is that
A. it needs very small current
B. it gives the average resistivity of the sample
C. it gives the resistivity at a localized region of the sample
D. it injects excess minority carriers

116. A normal atom is one which always has
A. equal number ofelectrons and protons
B. four valence electrons
C. an atomic core with charge of + 4q
D. shares its electrons with other atoms

117. The n-type impurity
A. must have only three valence electrons
B. creates excess holes
C. creates excess electrons
D. can be added to Ge but not Si

118. The conduction band is
A. always locatedat the top ofthe crystal
B. the same as forbidden energy gap
C. a range ofenergies coresponding to the energies of free electrons
D. not an allowed energy band

119. If arsenic impurity is added to germanium
A. it creates more holes
B. it causes free-electrons density to excess hole density
C. it causes increase in resistance of Ge sample
D. it results in new energy level just about valence level

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