| 1 |
Output of D.C. motor is |
- A. A.C. energy
- B. Mechanical energy
- C. Chemical energy
- D. D.C. energy
|
| 2 |
Commutator was invented by: |
- A. William bills
- B. William Gates
- C. William tells
- D. William Sturgeon
|
| 3 |
The jerks in D.C. motor are created by the use of. |
- A. Armature
- B. Commutators
- C. Split rings
- D. Source of emf
|
| 4 |
In a coil current change from 2 to 4 A in .05 s . If the average induced emf is 8 V then coefficient of self-inductance is: |
- A. 0.2 henry
- B. 0.1 henry
- C. 0.8 henry
- D. 0.04 henry
|
| 5 |
If the north pole of a magnet moves away from a metallic ring |
- A. Clockwise
- B. Anticlockwise
- C. First clockwise and then anticlockwise
- D. None of above
|
| 6 |
By winding the coil around a less magnetic core, self induction. |
- A. Will increase
- B. Will decrease
- C. Remain same
- D. First increase then decrease
|
| 7 |
Michael Faraday and Joseph Henry belongs to |
- A. England and USA
- B. France and USA
- C. China and USA
- D. None of these
|
| 8 |
A.C. Generator based upon the |
- A. Lenz's law
- B. Maxwell's relation
- C. Faradays law of electromagnet induction
- D. Mutual induction
|
| 9 |
What is the co-efficient of mutual inductance, when the magnetic flux changes by 2 x 10<sup>-2</sup> Wb, and change in current is 0.01 A? |
- A. 2 H
- B. 3 H
- C. 1/2 H
- D. Zero
|
| 10 |
If the coil is wound on iron core, the flux through it. |
- A. Decreases
- B. Becomes zero
- C. Increases
- D. Remains constant
|