64. Ripple factor is the ratio of value to value
A. r.m.s., peak
B. peak, D.C.
C. r.m.s., D.C.
D. peak, r.m.s.

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65. Higher value of ripple factor indicates
A. r.m.s. value equal to peak value
B. ideal rectification
C. poor rectification
D. none of the above

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66. The forward region of a semiconductor diode characteristic curve is where diode appears as
A. high resistance
B. an ON switch
C. and OFF switch
D. a capacitor

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67. The peak inverse voltage (PIV) is applied across a diode when it is
A. forward-biased
B. reversed-biased
C. on a heat sink
D. ON

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68. Which of the following statements is incorrect? Silicon diodes are used in rectifier circuit more abundantly chiefly because
A. they can stand higher temperature than germanium does
B. they cost much less than germanium diodes
C. their reverse current is much smaller than that of germanium diodes
D. their turn-off voltage is nearly half of germanium voltage

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69. A zener diode is invariably used with
A. reverse bias
B. forward bias
C. zero bias
D. any of the above

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70. A crystal diode is used as a
A. rectifier
B. amplifier
C. oscillator
D. any of the above

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