A fresh set of 20 random questions is generated every time you open this page and every time you refresh it.For each of the following multiple choice questions, choose the most appropriate answer :
1. Number of magnetic paths in a berry type transformer :
A. One
B. Two
C. Three
D. More than 3
2. Type of slot used in small DC Armature is :
A. Open type with tapered slot
B. Open type with Dove tail
C. Semi-enclosed type
D. Closed type
3. What is constructed from a length of flat thin sheet steel which is manufactured to form a tube?
A. Heavy gauge screwed conduit
B. Light gauge conduit
C. A and B
D. None of these
4. In induction motor, greater the number of poles
A. Lesser the speed
B. Greater the speed
C. Lesser the frequency
D. All of these
5. In a dc machine, the laminated parts are the armature core and
A. Pole shoes
B. Yoke
C. Shaft
D. base
6. A synchronous motor is switched on to supply with its field windings shorted on themselves. It will
A. not start
B. start and continue to run as an induction motor
C. start as an induction motor and then run as synchronous motor
D. bum immediately
7. Overhead system can be designed for operation upto :
A. 400 kV
B. 220 kV
C. 132 kV
D. 66 kV
8. The DC generator works on the principle of ?
A. Fleming’s left hand rule
B. Fleming’s right hand rule
C. Lenz’s law
D. None of these
9. Introduction of automation in production processes has become possible only because of use of :
A. An electrical drive
B. Group drive
C. Individual and multimotor drives
D. Individual drive
10. In any dc generators, the emf generated in the armature is maximum when
A. Flux linkage with conductors is maximum
B. Flux linkage with conductors is minimum
C. Rate of change of flux linkage is maximum
D. Rate of change of flux linkage is minimum
11. The starting torque and power factor of shaded pole induction motor
A. High, low
B. Low, high
C. Low, low
D. High, high
12. Power factor of a pure resistive circuit is equal to:
A. Zero
B. 1.0
C. 0.5
D. 0.8
13. The bulk modulus of a fluid is inversely proportional to the
A. Change in pressure
B. Volume of the fluid
C. Density of the fluid
D. Change in its volume
14. The intervals between wood plugs in batten wiring at intervals should not exceed :
A. 60 cm
B. 65 cm
C. 70 cm
D. 75 cm
15. The spit phase induction motor has
A. Low starting current and high starting torque
B. Moderate starting current and moderate starting torque
C. Low starting current and moderate starting torque
D. Moderate starting current and low starting torque
16. For a series motor, field flux is
A. Proportional to temperature
B. Constant
C. Proportional to armature current
D. Inversely proportional to armature current
17. A transistor is operated by :
A. current
B. voltage
C. both voltage and current
D. None of these
18. Impurities in an electrolyte can cause an internal short circuit condition called :
A. Depolarization
B. Electrolysis
C. Local action
D. Polarization
19. Link clips shall be so arranged that one single clip shall not hold more than two twin core TRS or PVC sheathed cables up to :
A. 0 sq mm
B. 3 sq mm
C. 5 sq mm
D. 6 sq mm
20. In AC relays, chattering noice can be reduced by :
A. Placing asbestos between the contacts
B. Providing a shading coil near the tip of magnetic field
C. Cleaning dirty particles over the coil and contacts
D. Applying varnish over coil core
Dr K Chaudhry 5 Alpha Inmternational City, Fatehabad 125050 M: 9810570740, 9810571993facebook.com/doctorkc