MCQOPTIONS
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MCQOPTIONS
This section includes 6 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Machines Questions and Answers knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
The starting method for a 3-phase squirrel-cage induction motor which is inferior in view of poor starting torque per ampere of line current drawn is? |
| A. | series-inductor method of starting |
| B. | direct-on-line starting |
| C. | auto-transformer method |
| D. | star-delta method |
| Answer» B. direct-on-line starting | |
| 2. |
A three phase induction motor is sometimes called a generalized transformer in so far as voltage and frequency transformation has been concerned. How a three phase induction motor operates when rotor frequency is less than stator frequency? |
| A. | It operates as induction motor |
| B. | Emf is induced in rotor |
| C. | Rmf will rotate at synchronous speed |
| D. | All of the mentioned |
| Answer» E. | |
| 3. |
Two three phase induction motors A and B are identical in all respects except that motor A has a larger air-gap than motor B. Which motor will have better full-load power factor? |
| A. | A |
| B. | B |
| C. | Both A and B |
| D. | Neither A nor B |
| Answer» C. Both A and B | |
| 4. |
Two three phase induction motors A and B are identical in all respects except that motor A has a larger air-gap than motor B. Which motor will have poorer power factor? |
| A. | A |
| B. | B |
| C. | Both A and B |
| D. | Neither A nor B |
| Answer» B. B | |
| 5. |
The direction of rmf when a three phase supply is given to stator of three phase induction motor is? |
| A. | Zero |
| B. | Ns |
| C. | 2Ns |
| D. | -Ns |
| Answer» C. 2Ns | |
| 6. |
The direction of rmf when a single phase supply is given to stator of three phase induction motor is? |
| A. | Zero |
| B. | Ns |
| C. | 2Ns |
| D. | -Ns |
| Answer» B. Ns | |