MCQOPTIONS
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MCQOPTIONS
This section includes 25 Mcqs, each offering curated multiple-choice questions to sharpen your Alternating Current and Voltage knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The starting torque of a single phase induction motor is |
| A. | high |
| B. | uniform |
| C. | zero. |
| D. | low |
| Answer» D. low | |
| 2. |
The motor used for driving the record player deck is |
| A. | synchronous motor |
| B. | dc series motor |
| C. | dc shunt motor. |
| D. | hysteresis motor |
| Answer» E. | |
| 3. |
A capacitor start single phase induction motor is switched on the supply with its capacitor replaced by an inductor of equivalent reactance value. It will |
| A. | start and run |
| B. | not start |
| C. | none of the above. |
| D. | start and then stall |
| Answer» C. none of the above. | |
| 4. |
The motor useful for signaling and timing device is |
| A. | Shaded pole motor |
| B. | Reluctance motor |
| C. | Two value capacitor motor. |
| D. | Hysteresis motor |
| Answer» C. Two value capacitor motor. | |
| 5. |
The starting torque of a capacitor start motor is |
| A. | low |
| B. | zero |
| C. | more than rated torque. |
| D. | same as rated torque |
| Answer» B. zero | |
| 6. |
Which of the following applications would need the smallest size of motor ? |
| A. | Electric clock |
| B. | Domestic motor |
| C. | Sewing machine. |
| D. | Table fan |
| Answer» B. Domestic motor | |
| 7. |
Reluctance motors are |
| A. | singly excited |
| B. | doubly excited |
| C. | none of the above. |
| D. | either doubly excited or singly excited |
| Answer» E. | |
| 8. |
When a universal motor is operated on no load, its speed is limited by |
| A. | armature weight |
| B. | armature reaction |
| C. | supply voltage frequency. |
| D. | windage and friction |
| Answer» E. | |
| 9. |
A capacitor start, capacitor run single phase induction motor is basically a |
| A. | dc series motor |
| B. | ac series motor |
| C. | 3 phase induction motor. |
| D. | 2 phase induction motor |
| Answer» E. | |
| 10. |
Under normal operating conditions which motor can run at 5000 rpm ? |
| A. | Induction motor |
| B. | Synchronous motor |
| C. | No motor can give 5000 rpm. |
| D. | Universal motor |
| Answer» E. | |
| 11. |
Which capacitor is preferred in case of single phase motor |
| A. | Ceramic capacitor |
| B. | Paper capacitor |
| C. | Electrolytic capacitor. |
| D. | Mica capacitor |
| Answer» D. Mica capacitor | |
| 12. |
Which of the following is non-reversible motor ? |
| A. | Capacitor start split phase motor |
| B. | Universal motor |
| C. | Permanent split capacitor motor. |
| D. | Resistance start split phase motor (D) |
| Answer» E. | |
| 13. |
A capacitor start single phase induction motor will usually have a power factor of |
| A. | 0.6 leading |
| B. | unity |
| C. | 0.6 lagging. |
| D. | 0.8 leading |
| Answer» D. 0.8 leading | |
| 14. |
What is the total current for a 5 MHz, 1 V ac circuit that consists of a 27 pF capacitor and a 1 k resistor connected in parallel? |
| A. | 459 A |
| B. | 647 A |
| C. | 1.31 mA |
| D. | 1.85 mA |
| Answer» D. 1.85 mA | |
| 15. |
If C 1 , a 4.7 F capacitor, and C 2 , a 3.3 F capacitor are in series with 18 V dc applied, what is the voltage across C 1 ? |
| A. | 3.3 V |
| B. | 7.4 V |
| C. | 6.6 V |
| D. | 9.4 V |
| Answer» C. 6.6 V | |
| 16. |
If a current of 40 mA flows through a series circuit consisting of a 0.4 F capacitor and a resistor in series with a 4 kHz, 40 V ac source, what is the total circuit impedance? |
| A. | 10 |
| B. | 100 |
| C. | 1 k |
| D. | 1 M |
| Answer» D. 1 M | |
| 17. |
What is the angle theta value for a 5.6 F capacitor and a 50-ohm resistor in series with a 1.1 kHz, 5 V ac source? |
| A. | 27.3 degrees |
| B. | 62.7 degrees |
| C. | –27.3 degrees |
| D. | –62.7 degrees |
| Answer» D. –62.7 degrees | |
| 18. |
In a 20 V ac series RC circuit, if 20 V is measured across the resistor and 40 V is measured across the capacitor, the applied voltage is: |
| A. | 45 V |
| B. | 50 V |
| C. | 55 V |
| D. | 60 V |
| Answer» B. 50 V | |
| 19. |
When the voltage across a capacitor is tripled, the stored charge |
| A. | triples |
| B. | is cut to one-third |
| C. | stays the same |
| D. | doubles |
| Answer» B. is cut to one-third | |
| 20. |
A 2 F, a 4 F, and a 10 F capacitor are connected in series. The total capacitance is less than |
| A. | 2 F |
| B. | 4 F |
| C. | 10 F |
| D. | 1.5 F |
| Answer» E. | |
| 21. |
A 330 pF capacitor and a 220 pF capacitor are each connected across a 6 V dc source. The voltage across the 330 pF capacitor is |
| A. | 3 V |
| B. | 6 V |
| C. | 4 V |
| D. | 0 V |
| Answer» C. 4 V | |
| 22. |
A 12 kHz voltage is applied to a 0.33 F capacitor, and 200 mA of rms current is measured. What is the value of the voltage? |
| A. | 8 V |
| B. | 80 V |
| C. | 80 mV |
| D. | 800 mV |
| Answer» B. 80 V | |
| 23. |
Of the following capacitors, which one has the highest dielectric constant? |
| A. | air |
| B. | mica |
| C. | glass |
| D. | paper |
| Answer» D. paper | |
| 24. |
A 220 resistor is in series with a 2.2 F capacitor. The time constant is |
| A. | 48 s |
| B. | 480 s |
| C. | 2.42 s |
| D. | 24 s |
| Answer» C. 2.42 s | |
| 25. |
A capacitor of 2,000 pF is greater than |
| A. | 0.02 F |
| B. | 0.002 F |
| C. | 0.0002 F |
| D. | 0.0000002 F |
| Answer» D. 0.0000002 F | |