Electrical Circuits Mid - II, April - 2012

1.In saturation region, Ic is_____.
  • zero
  • large
  • either low or zero
  • None
Answer: B
2.The Q-point is at cutoff for which power amplifier?
  • A
  • B
  • C
  • AB
Answer: B
3.Ic depends on which parameters?
  • VBE
  • Temperature
  • both a and b
  • None
Answer: C
4.Which class of amplifier operates in the linear region for only a small part of the input cycle?
  • A
  • B
  • AB
  • C
Answer: D
5.The hFE of a transistor ________ with temperature.
  • increases
  • decreases
  • does not vary
  • None
Answer: B
6.A clamping circuit consists of ___.
  • Resistor
  • Diode
  • both a and b
  • c and capacitor
Answer: D
7.A clipping circuit is also called as ____.
  • amplitude selector
  • limiting circuit
  • Amplitude slicer
  • all the above
Answer: D
8.Which of the following acts as a oscillator?
  • stable multivibrator
  • Monostable multivibrator
  • Bistable multivibrator
  • None of the above
Answer: A
9.A sinusoidal waveform can be converted to a square waveform by using
  • Astable multivibrator
  • Bistable multivibrator
  • Schmitt trigger
  • None of the above
Answer: C
10.A astable multivibrator is a __________.
  • Comparator
  • Voltage to frequency converter
  • counter
  • None of the above
Answer: B
11.Maximum efficiency of series-fed class-A amplifier is _________.
Answer: 25%
12.A heat sink provides ______ thermal resistance between case and air.
Answer: Low
13.A Class A amplifier has a voltage gain of 30 and a current gain of 25. What is power gain __________
Answer: 750
14.A clipping circuit may be used to convert a sine wave into a ________ wave.
Answer: Square wave
15.Regenerative comparators use which type of feedback _______________
Answer: positive
16.Sum of storage time and fall time of a transistor is called as ________.
Answer: Turn off time
17.Avalanche breakdown occurs due to ________.
Answer: Avalanche multiplication
18.The time constant of an astable multivibrator is ______.
Answer: 0.69RC
19.A bistable multivibrator is used for__________.
Answer: Counting and storing
20.In a free running multi vibrator, each stage is cut off for 1μs. What is the oscillator frequency ________
Answer: 0.5MHz