MCQOPTIONS
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MCQOPTIONS
This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Dc Machines knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
What will happen to a torque, if a DC series motor is accidentally connected to single phase ac supply voltage? |
| A. | Pulsating and unidirectional |
| B. | Steady and unidirectional |
| C. | Oscillating |
| D. | Cannot be determined |
| Answer» B. Steady and unidirectional | |
| 2. |
Practically, at higher values of armature current torque does not follow its relationship with armature current. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 3. |
Torque of e DC series motor is __________ |
| A. | Directly proportional to armature current |
| B. | Inversely proportional to armature current |
| C. | Directly proportional to square of armature current |
| D. | Inversely proportional to square of armature current |
| Answer» D. Inversely proportional to square of armature current | |
| 4. |
Actual speed obtained at any value of armature current comparing to speed obtained by assuming linear magnetic assumption in DC series motor is _______ |
| A. | Same |
| B. | Higher |
| C. | Lower |
| D. | Cannot say |
| Answer» C. Lower | |
| 5. |
Which of the following is the correct equation for DC series motor ________ |
| A. | [ V<sub>t</sub> / k<sub> </sub>]- [ R<sub>se</sub> +R<sub>a</sub> / k<sub> </sub>] I<sub>a</sub> |
| B. | [ V<sub>t</sub> / k<sub> </sub>]- [ R<sub>a</sub>/ k 2] Ia |
| C. | [ V<sub>t</sub> / k<sub> </sub><sup>2</sup>]- [R<sub>se</sub> +R<sub>a</sub>/ k<sub> </sub><sup>2</sup>] I<sub>a</sub> |
| D. | [ V<sub>t</sub> / k<sub> </sub><sup>2</sup>] + [ R<sub>a</sub>/ k<sub> </sub><sup>2</sup>] I<sub>a</sub> |
| Answer» B. [ V<sub>t</sub> / k<sub> </sub>]- [ R<sub>a</sub>/ k 2] Ia | |
| 6. |
Which DC motor has got maximum self-relieving property? |
| A. | Series motor |
| B. | Shunt motor |
| C. | Cumulatively compounded motor |
| D. | Differentially compounded motor |
| Answer» B. Shunt motor | |
| 7. |
DC motor is to drive a load which is having certain minimum value for most of the time and some peak value for short duration. We will select the _______ |
| A. | Series motor |
| B. | Shunt motor |
| C. | Compound motor |
| D. | Cannot be determined |
| Answer» B. Shunt motor | |
| 8. |
Buses, trains, trolleys, hoists, cranes make use of DC series motor because __________ |
| A. | It provides low starting torque |
| B. | Cost efficient |
| C. | It provides high starting torque |
| D. | It requires minimum power compare to other motors |
| Answer» D. It requires minimum power compare to other motors | |
| 9. |
Which DC motor is generally preferred for cranes and hoists? |
| A. | Series motor |
| B. | Shunt motor |
| C. | Cumulatively compounded motor |
| D. | Differentially compounded motor |
| Answer» B. Shunt motor | |