239. If a forward bias on a p-n junction is increased from zero, a rapid increase in current flow for a relatively small increase in voltage occurs
A. immediately
B. only after the forward bias exceeds the potential barrier
C. when the flow of minority carriers is sufficient to cause an avalanche break down
D. when the deplection area becomes larger than the space-charge area
240. When a forward bias is applied to a p-n junction, the minority-carrier density near the depletion layer
A. increase in the p-region and decreases in the n-region
B. decreases in the p-region and increases in the n-region
C. increases in both the p and n regions
D. decreases in both the p and n regions
241. Capacitance of a reverse-biased p-n junction
A. depends mainly on the reverse saturation current
B. increase as the reverse bias is increased
C. increases as the reverse bias is decreased
D. makes the p-n junction more effective at high frequencies
242. A junction diode
A. must have two p-n junctions
B. has one p-n junctions
C. is similar to a vacuum diode but cannot rectify
D. can handle only very small currents
243. In a p-n-p transistor with normal bias
A. only holes cross the collector junction
B. only majority carriers cross the collector junction
C. the collector junction has a low resistance
D. the emitter junction is forward-biased and the collector junction is reversebiased
244. In a n-p-n transistor with normal bias
A. only holes cross the collector junction
B. only majority carriers cross the collector junction
C. the collector junction has a low resistance
D. the emitter junction is forward-biased and the collector junction is reversebiased
245. In a transistor with normal bias, the emitter junction
A. has a high resistance is biasedwith the emitterpositive with respect to the base
B. has a low resistance
C.emits majority carriers into the base region
D.
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