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MCQOPTIONS
This section includes 1017 Mcqs, each offering curated multiple-choice questions to sharpen your Electronics & Communication Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
A transformer coupled amplifier would give |
| A. | maximum voltage gain |
| B. | impedance matching |
| C. | maximum current gain |
| D. | larger bandwidth |
| Answer» C. maximum current gain | |
| 152. |
Transformer coupling can be used in amplifiers |
| A. | only power |
| B. | only voltage |
| C. | either power or voltage |
| D. | neither power nor voltage |
| Answer» D. neither power nor voltage | |
| 153. |
Improvement in production techniques of power transistors have . |
| A. | produced higher power ratings in small-sized packaging cases |
| B. | increased the maximum transistor breakdown voltage |
| C. | provided faster- switching power transistors |
| D. | all of the above |
| Answer» E. | |
| 154. |
What is the purpose of the emitter capacitor? |
| A. | to forward bias the emitter |
| B. | to reduce noise in the amplifier |
| C. | to avoid drop in gain |
| D. | to stabilize emitter voltage |
| Answer» D. to stabilize emitter voltage | |
| 155. |
The main features of a large-signal amplifier is the circuit's . |
| A. | power efficiency |
| B. | maximum power limitations |
| C. | impedance matching to the output device |
| D. | all of the above |
| Answer» E. | |
| 156. |
The decibel gain of a cascaded amplifier equals to |
| A. | product of individual gains |
| B. | sum of individual gains |
| C. | ration of stage gains |
| D. | product of voltage and current gains |
| Answer» C. ration of stage gains | |
| 157. |
The Q-point is at cutoff for class operation. |
| A. | a |
| B. | b |
| C. | c |
| D. | ab |
| Answer» C. c | |
| 158. |
transistors can be used to build a class B amplifier. |
| A. | npn and pnp |
| B. | nmos and pmos |
| C. | both npn and pnp or nmos and pmos |
| D. | none of the above |
| Answer» D. none of the above | |
| 159. |
A heat sink provides thermal resistance between case and air. |
| A. | a high |
| B. | a low |
| C. | the same |
| D. | none of the above |
| Answer» C. the same | |
| 160. |
The output voltage of a CE amplifier is |
| A. | amplified |
| B. | inverted |
| C. | 180° out of phase with the input |
| D. | all of the above |
| Answer» E. | |
| 161. |
The circuit has resistors, capacitors and semi-conductor diodes. The circuit will be known as |
| A. | non-linear circuit |
| B. | linear circuit |
| C. | bilateral circuit |
| D. | none of the above |
| Answer» B. linear circuit | |
| 162. |
In power amplifiers, the output signal varies for a full 360º of the cycle. |
| A. | class a |
| B. | class b or ab |
| C. | class c |
| D. | class d |
| Answer» B. class b or ab | |
| 163. |
Which of the power amplifiers is not intended primarily for large- signal or power amplification? |
| A. | class a |
| B. | class b or ab |
| C. | class c |
| D. | class d |
| Answer» D. class d | |
| 164. |
The BJT is a device. The FET is a device. |
| A. | bipolar, bipolar |
| B. | bipolar, unipolar |
| C. | unipolar, bipolar |
| D. | unipolar, unipolar |
| Answer» C. unipolar, bipolar | |
| 165. |
"Maximum power output is obtained from a network when the load resistance is equal to the output resistance of the network as seen from the terminals of the load". The above statement is associated with |
| A. | mill man’s theorem |
| B. | thevenin\s theorem |
| C. | superposition theorem |
| D. | maximum power transfer theorem |
| Answer» E. | |
| 166. |
The output of a class-B amplifier |
| A. | is distortion free |
| B. | consists of positive half cycle only |
| C. | is like the output of a full wave rectifier |
| D. | comprises short duration current pulses |
| Answer» C. is like the output of a full wave rectifier | |
| 167. |
Transmit time is the time taken by the electrons on holes to pass from |
| A. | emitter to collector |
| B. | collector to emitter |
| C. | base to emitter |
| D. | base to collector |
| Answer» B. collector to emitter | |
| 168. |
The major advantage of CMOS logic circuits over TTL is |
| A. | very low power consumption. |
| B. | the ability to produce several output voltage levels. |
| C. | lower propagation delay. |
| D. | much higher propagation delay. |
| Answer» B. the ability to produce several output voltage levels. | |
| 169. |
An ideal differential amplifiers common mode rejection ratio is |
| A. | infinite |
| B. | zero |
| C. | unity |
| D. | undetermined |
| Answer» B. zero | |
| 170. |
When transistors are used in digital circuits they usually operate in the |
| A. | active region |
| B. | breakdown region |
| C. | saturation and cutoff regions |
| D. | linear region |
| Answer» D. linear region | |
| 171. |
Which of the item below does not describe a common emitter amplifier? |
| A. | high voltage gain |
| B. | high current gain |
| C. | very high power gain |
| D. | high input resistance |
| Answer» E. | |
| 172. |
According to Kirchhoffs voltage law, the algebraic sum of all IR drops and e.m.fs. in any closed loop of a network is always |
| A. | negative |
| B. | positive |
| C. | determined by battery e.m.fs. |
| D. | zero |
| Answer» E. | |
| 173. |
For any inverting amplifier, the impedance capacitance will be by a Miller effect capacitance sensitive to the gain of the amplifier and the interelectrode capacitance. |
| A. | unaffected |
| B. | increased |
| C. | decreased |
| D. | none of the above |
| Answer» D. none of the above | |
| 174. |
Minimum interference with frequency response can be given by |
| A. | direct coupling |
| B. | rc coupling |
| C. | transformer coupling |
| D. | instrumentation and control |
| Answer» B. rc coupling | |
| 175. |
Heat sinks reduce the |
| A. | transistor power |
| B. | ambient temperature |
| C. | junction temperature |
| D. | collector current |
| Answer» D. collector current | |
| 176. |
For highest power gain, what configuration is used? |
| A. | cc |
| B. | cb |
| C. | ce |
| D. | cs |
| Answer» D. cs | |
| 177. |
The capacitors are considered in the ac equivalent circuit of a transistor amplifier. |
| A. | open |
| B. | partially open |
| C. | short |
| D. | partially short |
| Answer» D. partially short | |
| 178. |
In Fourier technique, any periodic distorted waveform can be represented by the fundamental and all harmonic components. |
| A. | multiplying |
| B. | subtracting |
| C. | dividing |
| D. | adding |
| Answer» E. | |
| 179. |
The of a common collector configuration is unity |
| A. | voltage gain |
| B. | current gain |
| C. | power gain |
| D. | input impedance |
| Answer» B. current gain | |
| 180. |
If the capacitor from emitter to ground in a common emitter amplifier is removed, the voltage gain |
| A. | increases |
| B. | decreases |
| C. | becomes erratic |
| D. | remains the same |
| Answer» C. becomes erratic | |
| 181. |
Power amplifiers handle signals compare to voltage amplifiers. |
| A. | small |
| B. | very small |
| C. | large |
| D. | none of the above |
| Answer» D. none of the above | |
| 182. |
Which of the following configurations does not involve the Miller effect capacitance? |
| A. | common-emitter |
| B. | common-base |
| C. | common- collector |
| D. | all of the above |
| Answer» C. common- collector | |
| 183. |
A 35 mV signal is applied to the base of a properly biased transistor with an r'e = 8 Ω and RC = 1 kΩ. The output signal voltage at the collector is: |
| A. | 3.5 v |
| B. | 28.57 v |
| C. | 4.375 v |
| D. | 4.375 mv |
| Answer» D. 4.375 mv | |
| 184. |
The common base (CB) amplifier has a compared to CE and CC amplifier. |
| A. | lower input resistance |
| B. | larger current gain |
| C. | larger voltage gain |
| D. | higher input resistance |
| Answer» B. larger current gain | |
| 185. |
The maximum current for a HIGH output on a standard TTL gate is |
| A. | -10 µa. |
| B. | -400 µa. |
| C. | -1 µa. |
| D. | -10 ma. |
| Answer» C. -1 µa. | |
| 186. |
The output transformer used in a power amplifier is a/an transformer |
| A. | 1:1 ratio |
| B. | step-down |
| C. | step-up |
| D. | isolation |
| Answer» C. step-up | |
| 187. |
The JFET is always operated with the gate-source pn junction -biased. |
| A. | forward |
| B. | reverse |
| C. | all of the above |
| D. | none of the above |
| Answer» C. all of the above | |
| 188. |
Class C amplifiers are used as |
| A. | af amplifiers |
| B. | small signal amplifiers |
| C. | rf amplifiers |
| D. | if amplifiers |
| Answer» D. if amplifiers | |
| 189. |
The output power of a transistor amplifier is more than the input power due to additional power supplied by |
| A. | transistor |
| B. | collector supply |
| C. | emitter supply |
| D. | base supply |
| Answer» C. emitter supply | |
| 190. |
What is the ratio of the secondary voltage to the primary voltage with the turn ratio in the winding |
| A. | n2/n1 |
| B. | (n1/n2)2 |
| C. | (n1/n2)1/3 |
| D. | n1 × n2 |
| Answer» B. (n1/n2)2 | |
| 191. |
An emitter follower has a voltage gain that is |
| A. | much less than one |
| B. | approximately equal to one |
| C. | greater than one |
| D. | zero |
| Answer» C. greater than one | |
| 192. |
coupling is generally employed in power amplifiers |
| A. | transformer |
| B. | rc |
| C. | direct |
| D. | impedance |
| Answer» B. rc | |
| 193. |
For normal operation of a pnp BJT, the base must be with respect to the emitter and with respect to the collector. |
| A. | positive, negative |
| B. | positive, positive |
| C. | negative, positive |
| D. | negative, negative |
| Answer» D. negative, negative | |
| 194. |
The complementary Darlington-connected transistor for a class B amplifier provides output current and output resistance. |
| A. | higher, higher |
| B. | higher, lower |
| C. | lower, lower |
| D. | lower, higher |
| Answer» C. lower, lower | |
| 195. |
Ina common emitter amplifier, the capacitor from emitter to ground is called the |
| A. | coupling capacitor |
| B. | bypass capacitor |
| C. | decoupling capacitor |
| D. | tuning capacitor |
| Answer» C. decoupling capacitor | |
| 196. |
Kirchhoff’s current law is applicable only to |
| A. | junction in a network |
| B. | closed loops in a network |
| C. | electric circuits |
| D. | electronic circuits |
| Answer» B. closed loops in a network | |
| 197. |
The extremely high input impedance of a MOSFET is primarily due to the |
| A. | absence of its channel |
| B. | negative gate- source voltage |
| C. | depletion of current carriers |
| D. | extremely small leakage current of its gate capacitor |
| Answer» E. | |
| 198. |
The lower transistor of a totem-pole output is saturated when the gate output is |
| A. | high. |
| B. | low. |
| C. | malfunctioning. |
| D. | over driven. |
| Answer» C. malfunctioning. | |
| 199. |
What is the purpose of dc conditions in a transistor? |
| A. | to reverse bias the emitter |
| B. | to forward bias the emitter |
| C. | to set up operating point |
| D. | to turn on the transistor |
| Answer» D. to turn on the transistor | |
| 200. |
The highest efficiency is obtained in class B operation when the level of VL(p) is equal to . |
| A. | 0.25vcc |
| B. | 0.50vcc |
| C. | vcc |
| D. | 2vcc |
| Answer» D. 2vcc | |