

MCQOPTIONS
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This section includes 29 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.
1. |
The piezoelectric effect in a crystal is ___________%! |
A. | A voltage developed because of mechanical stress |
B. | A change in resistance because of temperature |
C. | A change in frequency because of temperature |
D. | None of the above |
Answer» B. A change in resistance because of temperature | |
2. |
In an LC oscillator, if the value of L is increased four times, the frequency of oscillations is ___________%! |
A. | Increased 2 times |
B. | Decreased 4 times |
C. | Increased 4 times |
D. | Decreased 2 times |
Answer» E. | |
3. |
A second condition for oscillations is ___________%! |
A. | A gain of 1 around the feedback loop |
B. | No gain around the feedback loop |
C. | The attention of the feedback circuit must be one-third |
D. | The feedback circuit must be capacitive |
Answer» B. No gain around the feedback loop | |
4. |
*$_The crystal oscillator frequency is very stable due to ___________ of the crystal? |
A. | Rigidity |
B. | Vibrations |
C. | Low Q |
D. | High Q |
Answer» E. | |
5. |
*/*_An oscillator employs ___________ feedback? |
A. | Positive |
B. | Negative |
C. | Neither positive nor negative |
D. | Data insufficient |
Answer» B. Negative | |
6. |
*/*_In an LC circuit, when the capacitor is maximum, the inductor energy is ___________? |
A. | Minimum |
B. | Maximum |
C. | Half-way between maximum and minimum |
D. | None of the above |
Answer» B. Maximum | |
7. |
*/*_In a phase shift oscillator, the frequency determining elements are ___________? |
A. | L and C |
B. | R, L and C |
C. | R and C |
D. | None of the above |
Answer» D. None of the above | |
8. |
*/*_In a Wien-bridge oscillator, if the resistances in the positive feedback circuit are decreased, the frequency ___________? |
A. | Remains the same |
B. | Decreases |
C. | Increases |
D. | Insufficient data |
Answer» D. Insufficient data | |
9. |
%_Hartley oscillator is commonly used in ____________% |
A. | Radio receivers |
B. | Radio transmitters |
C. | TV receivers |
D. | None of the above |
Answer» B. Radio transmitters | |
10. |
__The signal generator generally used in the laboratories is ___________ oscillator__ |
A. | Wien-bridge |
B. | Hartely |
C. | Crystal |
D. | Phase shift |
Answer» B. Hartely | |
11. |
__An important limitation of a crystal oscillator is _____________ |
A. | Its low output |
B. | Its high Q |
C. | Less availability of quartz crystal |
D. | Its high output |
Answer» B. Its high Q | |
12. |
__An oscillator converts _____________ |
A. | a.c. power into d.c. power |
B. | d.c. power into a.c. power |
C. | mechanical power into a.c. power |
D. | none of the above |
Answer» C. mechanical power into a.c. power | |
13. |
__If the crystal frequency changes with temperature, we say that crystal has ___________ temperature coefficient__ |
A. | Positive |
B. | Zero |
C. | Negative |
D. | None of the above |
Answer» B. Zero | |
14. |
_In a certain oscillator Av = 50. The attention of the feedback circuit must be ___________$? |
A. | 1 |
B. | 1 |
C. | 10 |
D. | 2 |
Answer» E. | |
15. |
In a phase shift oscillator, we use ___________ RC sections$? |
A. | Two |
B. | Three |
C. | Four |
D. | None of the above |
Answer» C. Four | |
16. |
The application where one would most likely find a crystal oscillator is ___________$? |
A. | Radio receiver |
B. | Radio transmitter |
C. | AF sweep generator |
D. | None of the above |
Answer» C. AF sweep generator | |
17. |
One condition for oscillation is ___________$? |
A. | A phase shift around the feedback loop of 180° |
B. | A gain around the feedback loop of one-third |
C. | A phase shift around the feedback loop of 0° |
D. | A gain around the feedback loop of less than 1 |
Answer» D. A gain around the feedback loop of less than 1 | |
18. |
The Q of the crystal is of the order of ___________$? |
A. | 100 |
B. | 1000 |
C. | 50 |
D. | More than 10,000 |
Answer» E. | |
19. |
Quartz crystal is most commonly used in crystal oscillators because ___________$? |
A. | It has superior electrical properties |
B. | It is easily available |
C. | It is quite inexpensive |
D. | None of the above |
Answer» B. It is easily available | |
20. |
Quartz crystal is most commonly used in crystal oscillators because ___________? |
A. | It has superior electrical properties |
B. | It is easily available |
C. | It is quite inexpensive |
D. | None of the above |
Answer» B. It is easily available | |
21. |
An LC oscillator cannot be used to produce ___________ frequencies |
A. | High |
B. | Audio |
C. | Very low |
D. | Very high |
Answer» D. Very high | |
22. |
___________ is a fixed frequency oscillator |
A. | Phase-shift oscillator |
B. | Hartely-oscillator |
C. | Colpitt's oscillator |
D. | Crystal oscillator |
Answer» E. | |
23. |
An oscillator differs from an amplifier because it |
A. | Has more gain |
B. | Requires no input signal |
C. | Requires no d.c. supply |
D. | Always has the same input |
Answer» C. Requires no d.c. supply | |
24. |
For an oscillator to properly start, the gain around the feedback loop must initially be |
A. | 1 |
B. | Greater than 1 |
C. | Less than 1 |
D. | Equal to attenuation of feedback circuit |
Answer» C. Less than 1 | |
25. |
In an LC oscillator, the frequency of oscillator is ___________ L or C. |
A. | Proportional to square of |
B. | Directly proportional to |
C. | Independent of the values of |
D. | Inversely proportional to square root of |
Answer» E. | |
26. |
An oscillator produces___________ oscillations |
A. | Damped |
B. | Undamped |
C. | Modulated |
D. | None of the above |
Answer» C. Modulated | |
27. |
In an LC transistor oscillator, the active device is ___________ |
A. | LC tank circuit |
B. | Biasing circuit |
C. | Transistor |
D. | None of the above |
Answer» D. None of the above | |
28. |
A Wien bridge oscillator uses ___________ feedback |
A. | Only positive |
B. | Only negative |
C. | Both positive and negative |
D. | None of the above |
Answer» D. None of the above | |
29. |
In Colpitt's oscillator, feedback is obtained ___________ |
A. | By magnetic induction |
B. | By a tickler coil |
C. | From the centre of split capacitors |
D. | None of the above |
Answer» D. None of the above | |