| 1 |
Efficiency of transformer does not affected by |
- A. Input voltage
- B. Core of transformer
- C. Insulation between sheet
- D. Resistance of coils
|
| 2 |
The Si unit of Mutual inductance is: |
- A. VA<sup>-1</sup>S<sup>-1</sup>
- B. VAS<sup>-1</sup>
- C. VSA<sup>-1</sup>
- D. ASV<sup>-1</sup>
|
| 3 |
The unit of induced emf is |
- A. Ampere
- B. Volt
- C. Joule/coulomb
- D. Both (b) and (c)
|
| 4 |
If D.C. input for step up transformer, the output is |
- A. Zero
- B. High
- C. Low
- D. May be high or low
|
| 5 |
If speed of rotation of a generator is doubled the output voltage will be. |
- A. Remain same
- B. Double
- C. Four time
- D. One half
|
| 6 |
Which of the following converts electrical energy into mechanical energy. |
- A. Transformer
- B. A.C. generator
- C. D.C. generator
- D. D.C. motor
|
| 7 |
the core of transformer is laminated so reduce. |
- A. Magnetic loss
- B. Hysteresis loss
- C. Eddy current loss
- D. Electric loss
|
| 8 |
A simple device that prevents the direction of current from changing is called. |
- A. Commutator
- B. Rotor
- C. Armature
- D. Detector
|
| 9 |
The movement of conductor in magnetic field produces electrical current was discovered in: |
- A. 1931
- B. 1731
- C. 1842
- D. 1831
|
| 10 |
When a motor is over loaded then the magnitude of back emf. |
- A. Increases
- B. Decreases
- C. Remain constant
- D. Zero
|