155. In a PNP transistor, with normal bias
A. the collector junction has negligible resistance
B. only holes cross the collector junction
C. the collector-base junction is reverse biased and the emitter base junction is forward biased
D. only majority carriers cross the collector junction.

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156.  In a NPN transistor the function of the emitter is
A. to emit or inject holes into the collector
B. to emit or inject electrons into the collector
C. to emit or inject electrons into the base
D. to emit or inject holes into the base.

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157.  In a PNP transistor, with normal bias, the emitter junction
A. is always reverse biased
B. offers very high resistance
C. offers a low resistance
D. remains open

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158.  In a NPN transistor, when emitter junction is forward biased and collector junction is reverse biased, the transistor will operate in
A. active region
B. saturation region
C. cut off region
D. inverted region

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159. Which of the following statement is correct?
A. FET and junction transistor both are unipolar
B. FET and junction transistor both are bipolar
C. The FET is bipolar, while junction transistors are unipolar
D. The FET is unipolar, while junction transistors are bipolar.

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160. A transistor may fail due to
A. open weld at the wire leads to the semiconductor
B. short circuit caused by momentary overload
C. overheating due to circuit failures
D. any of the above

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161. Arrow head on a transistor symbol indicates
A. Direction of electron current in emitter
B. Direction of hole current in emitter
C. Diffusion current in emitter
D. Drift current in emitter

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