MCQOPTIONS
Saved Bookmarks
MCQOPTIONS
This section includes 9294 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 2251. |
In a CE amplifier the collector resistance is short circuited. The ac output voltage will |
| A. | increases |
| B. | remains the same |
| C. | increases or decreases |
| D. | decreases |
| Answer» E. | |
| 2252. |
In a CE amplifier |
| A. | both ac and dc load lines have the same slope |
| B. | the ac load line has more slope than dc load line |
| C. | the ac load line has less slope than dc load line |
| D. | the two load lines may have slope more than the other |
| Answer» C. the ac load line has less slope than dc load line | |
| 2253. |
The voltage gain of an amplifier without and with feedback are 100 and 20. The negative feedback is |
| A. | 4% |
| B. | 5% |
| C. | 20% |
| D. | 80% |
| Answer» B. 5% | |
| 2254. |
In the circuit shown in figure, RC = 10k, RE = 150Ω, = 100, I = 1 mA. The value of , will be |
| A. | 50 |
| B. | 100 |
| C. | 192 |
| D. | 400 |
| Answer» D. 400 | |
| 2255. |
A potential of 7 V is applied to a silicon diode. A resistance of 1 kΩ is also connected in series. If the diode is forward biased, the current in the circuit is |
| A. | 7 mA |
| B. | 6.3 mA |
| C. | 0.7 mA |
| D. | 0 |
| Answer» C. 0.7 mA | |
| 2256. |
The inverting op-amp shown in the figure has an open loop gain to 100. The closed loop given is |
| A. | -8 |
| B. | -9 |
| C. | -10 |
| D. | -11 |
| Answer» E. | |
| 2257. |
The parameter h11 for CB circuit is higher than that for CE circuit. |
| A. | True |
| B. | False |
| Answer» C. | |
| 2258. |
Figure shows a self bias circuit for FET amplifier, ID = 4 mA. Then IS = |
| A. | 4 mA |
| B. | 2 mA |
| C. | 0.4 mA |
| D. | 0.2 mA |
| Answer» B. 2 mA | |
| 2259. |
In the CE equivalent circuit of figure, the voltage gain is |
| A. | 200 |
| B. | 40 |
| C. | 5 |
| D. | 1000 |
| Answer» B. 40 | |
| 2260. |
In figure the zener current |
| A. | is always 130 mA |
| B. | may vary between 10 mA and 130 mA |
| C. | may vary between 60 mA and 130 mA |
| D. | is always equal to 65 mA |
| Answer» C. may vary between 60 mA and 130 mA | |
| 2261. |
In a commercially available good power supply the voltage regulation is about |
| A. | 1% |
| B. | 5% |
| C. | 10% |
| D. | 20% |
| Answer» B. 5% | |
| 2262. |
If the differential voltage gain and the common mode voltage gain of a differential amplifier are 48 dB and 2 dB respectively, then its common mode rejection ratio is |
| A. | 23 dB |
| B. | 25 dB |
| C. | 46 dB |
| D. | 50 dB |
| Answer» D. 50 dB | |
| 2263. |
If input frequency is 50 Hz, the frequency of output wave in a full wave diode rectifier circuit is |
| A. | 25 Hz |
| B. | 50 Hz |
| C. | 100 Hz |
| D. | 200 Hz |
| Answer» D. 200 Hz | |
| 2264. |
An npn transistor has a Beta cutoff frequency f of 1 MHz, and a common emitter short circuit low frequency current gain 0 of 200. It unity gain frequency fT and the alpha cut off frequency fa2 respectively are |
| A. | 200 MHz, 201 MHz |
| B. | 200 MHz, 199 MHz |
| C. | 199 MHz, 200 MHz |
| D. | 201 MHz, 200 MHz |
| Answer» B. 200 MHz, 199 MHz | |
| 2265. |
An amplifier has open loop gain of 100, input impedance 1 kΩ and output impedance 100 Ω. If negative feedback with = 0.99 is used, the new input and output impedances are |
| A. | 10 Ω and 1 Ω |
| B. | 10 Ω and 10 kΩ |
| C. | 100 kΩ and 1 Ω |
| D. | 100 kΩ and 10 Ω |
| Answer» D. 100 kΩ and 10 Ω | |
| 2266. |
A class A transformer coupled power amplifier is to deliver 10 W output. The power rating of transistor should not be less than |
| A. | 5 W |
| B. | 10 W |
| C. | 20 W |
| D. | 40 W |
| Answer» D. 40 W | |
| 2267. |
In figure, secondary winding has 40 turns. For maximum power transformer to 2 ohm resistance the number of turns in primary is |
| A. | 20 |
| B. | 40 |
| C. | 80 |
| D. | 160 |
| Answer» D. 160 | |
| 2268. |
In a CE amplifier circuit the dc voltage between emitter and ground |
| A. | is always zero |
| B. | cannot be zero |
| C. | may or may not be zero |
| D. | is negative |
| Answer» C. may or may not be zero | |
| 2269. |
A half wave diode rectifier uses a diode having forward resistance of 50 ohms. The load resistance is also 50 ohms. Then the voltage regulation is |
| A. | 20% |
| B. | 50% |
| C. | 100% |
| D. | 200% |
| Answer» D. 200% | |
| 2270. |
A Hartley oscillator is used for |
| A. | very low frequencies |
| B. | radio frequencies |
| C. | micro wave frequencies |
| D. | audio frequency |
| Answer» C. micro wave frequencies | |
| 2271. |
Assuming VCE sat = 0.2 V and = 50, the minimum base current (IB) required to drive the transistor in the given figure to saturation is |
| A. | 56 A |
| B. | 140 A |
| C. | 60 A |
| D. | 3 A |
| Answer» B. 140 A | |
| 2272. |
An op-amp integrating circuit uses |
| A. | an inductor |
| B. | a capacitor |
| C. | both inductor and capacitor |
| D. | none of the above |
| Answer» C. both inductor and capacitor | |
| 2273. |
In Class C operation the collector current looks like |
| A. | full sine wave |
| B. | half sine wave |
| C. | narrow pulses |
| D. | nearly half sine wave |
| Answer» D. nearly half sine wave | |
| 2274. |
In figure base current is 10 A and dc = 100. Then VE = |
| A. | 5 V |
| B. | 10 V |
| C. | 15 V |
| D. | 20 V |
| Answer» D. 20 V | |
| 2275. |
It has been found that in a rectifier circuit with RC filter one RC section reduces ripple by 15%. Two RC sections are used in cascade the reduction in ripple would be |
| A. | 15% |
| B. | 30% |
| C. | 150% |
| D. | 225% |
| Answer» E. | |
| 2276. |
An op-amp has |
| A. | low input and output impedance |
| B. | low input impedance and high output impedance |
| C. | low output impedance and high input impedance |
| D. | high output impedance and high input impedance |
| Answer» D. high output impedance and high input impedance | |
| 2277. |
As the ratio Rf/RL increases the efficiency of a rectifier increases. |
| A. | True |
| B. | False |
| Answer» C. | |
| 2278. |
A negative feedback can be of |
| A. | 2 types |
| B. | 3 types |
| C. | 4 types |
| D. | only 1 type |
| Answer» D. only 1 type | |
| 2279. |
In a class C power amplifier the input frequency of ac signal is 1 MHz. If tank circuit has C = 1000 pF, the value of L = |
| A. | 25 H |
| B. | 50 H |
| C. | 100 H |
| D. | 200 H |
| Answer» B. 50 H | |
| 2280. |
In calculating output impedance of an amplifier the source is replaced by an open circuit. |
| A. | True |
| B. | False |
| Answer» C. | |
| 2281. |
For transistor 2 N 338 the manufacturer specifies Pmax = 100 mW at 250 C free air temperature and maximum junction temperature of 125 C. Its thermal resistance is |
| A. | 10 C/W |
| B. | 100 C/W |
| C. | 1000 C/W |
| D. | 5000 C/W |
| Answer» D. 5000 C/W | |
| 2282. |
In the op-amp circuit given in the figure, the load current iL is |
| A. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/333-520-2.png"> |
| B. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/333-520-3.png"> |
| C. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/333-520-4.png"> |
| D. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/333-520-5.png"> |
| Answer» B. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/333-520-3.png"> | |
| 2283. |
Assertion (A): An op-amp has high voltage gain, high input impedance and low output impedanceReason (R): Negative feedback increases output impedance |
| A. | Both A and R are correct and R is correct explanation for A |
| B. | Both A and R are correct but R is not correct explanation for A |
| C. | A is correct R is wrong |
| D. | A is wrong R is correct |
| Answer» D. A is wrong R is correct | |
| 2284. |
A transistor has a maximum power dissipation of 350 mW at an ambient temperature of 25 C. If derating factor is 2 mW/ C, the maximum power dissipation for 40 C ambient temperature is |
| A. | 300 mW |
| B. | 330 mW |
| C. | 350 mW |
| D. | 380 mW |
| Answer» D. 380 mW | |
| 2285. |
The output voltage waveform of a CE amplifier is fed to a dc coupled CRO. The trace on the screen will be |
| A. | dc output voltage |
| B. | ac output voltage |
| C. | sum of dc and ac output voltage |
| D. | either (a) or (b) |
| Answer» D. either (a) or (b) | |
| 2286. |
In the circuit of figure = 100 and quiescent value of base current is 20 A. The quiescent value of collector current is |
| A. | 0.2 A |
| B. | 2 A |
| C. | 2 mA |
| D. | 20 mA |
| Answer» D. 20 mA | |
| 2287. |
In an RC phase shift oscillator, the total phase shift of the three RC lead networks is |
| A. | 360 |
| B. | 180 |
| C. | 90 |
| D. | 0 |
| Answer» C. 90 | |
| 2288. |
A 120 V, 30 Hz source feeds a half wave rectifier circuit through a 4 : 1 step down transformer, the average output voltage is |
| A. | 30 V |
| B. | 13.5 V |
| C. | 10 V |
| D. | 7.07 V |
| Answer» C. 10 V | |
| 2289. |
The slew rate of an ideal op-amp is |
| A. | very slow |
| B. | slow |
| C. | fast |
| D. | infinitely fast |
| Answer» E. | |
| 2290. |
Which of the following can be used as a buffer amplifier? |
| A. | CE |
| B. | CC |
| C. | CB |
| D. | Both (a) and (c) |
| Answer» C. CB | |
| 2291. |
In figure the approximate voltages of |
| A. | base and emitter are - 8 V and - 7.3 V |
| B. | base and collector are - 8 V and - 5 V |
| C. | collector and emitter are - 5 V and - 7.3 V |
| D. | base, emitter and collector are - 8, - 7.3 and - 5 V |
| Answer» B. base and collector are - 8 V and - 5 V | |
| 2292. |
The feedback technique employed in the following circuit is |
| A. | voltage series feedback |
| B. | current series feedback |
| C. | voltage shunt feedback |
| D. | current shunt feedback |
| Answer» D. current shunt feedback | |
| 2293. |
In figure the voltage drop across diode is 0.7 V. Then the voltage across diode during negative half cycle is |
| A. | 10 V |
| B. | 9.3 V |
| C. | zero |
| D. | 10.7 V |
| Answer» B. 9.3 V | |
| 2294. |
The open loop gain of an amplifier is 50 but likely to decrease by 20% due to various factors. If negative feedback with = 0.1 is used, the change in gain will be about |
| A. | 20% |
| B. | 2% |
| C. | 0.5% |
| D. | 0.05% |
| Answer» D. 0.05% | |
| 2295. |
In figure vi = 10 mV dc maximum. The maximum possible dc output offset voltage is |
| A. | 60 mV dc |
| B. | 110 mV dc |
| C. | 130 mV dc |
| D. | 150 mV dc |
| Answer» C. 130 mV dc | |
| 2296. |
For the circuit of figure the critical frequency is |
| A. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/325-392-2.png"> |
| B. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/325-392-3.png"> |
| C. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/325-392-4.png"> |
| D. | <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/325-392-5.png"> |
| Answer» C. <img src="/_files/images/electronics-and-communication-engineering/analog-electronics/325-392-4.png"> | |
| 2297. |
The current through R1 is(If = 99, VBE = 0.74 V) |
| A. | 0.1 mA |
| B. | 0.35 mA |
| C. | 0.2 mA |
| D. | none |
| Answer» B. 0.35 mA | |
| 2298. |
A buffer amplifier should have |
| A. | high input impedance and low output impedance |
| B. | high input impedance and high output impedance |
| C. | low input impedance and high output impedance |
| D. | low input impedance and low output impedance |
| Answer» B. high input impedance and high output impedance | |
| 2299. |
In a CE amplifier, the output voltage is equal to product of |
| A. | ac collector current and ac collector resistance |
| B. | ac base current and ac collector resistance |
| C. | ac emitter current and ac emitter resistance |
| D. | ac collector current and source resistance |
| Answer» B. ac base current and ac collector resistance | |
| 2300. |
Heat sink results in |
| A. | slower dissipation of heat to atmosphere |
| B. | faster dissipation of heat to atmosphere |
| C. | lower ambient temperature |
| D. | lower transistor power |
| Answer» C. lower ambient temperature | |