Some Important MCQ for Electrical Students
1. The basic elements of an electric drive are
(a) electric motor and the transmission system .
(b) electric motor, the transmission and control system .
(c) the transmission and control system.
(d) electric motor and conversion equipment.
2. Electric drive is becoming more and more popular because
(a) it simple, clean, compact and reliable.
(b) it provides easy and smooth control, flexibility in layout ,easy starting and facility for remote control
(c) it is cheaper in initial as well as in maintenance cost
(d) all of the above
3. The main drawback of electric drive is that
(a) it is cumbersome drive
(b) it is costlier in initial as well as in
maintenance cost
(c) Electrical power supply failure makes the drive standstill
(d) all of the above
4. An existing workshop is to be changed over from an engine drive to an electric drive . The type of drive likely to be adopted
(a) individual drive
(b) group drive
(c) multi-motor drive
(d) any of the above
5. The type of drive used for a paper mill requiring constant speed operation and flexibility of control is
(a) group drive
(b) multi-motor
(c) individual drive or multimulti-motor
(d) individual drive
6. Introduction of automation in production of processes has become possible only because of use of
(a) an electric drive
(b) group drive
(c) individual drive or multi-motor drive
(d) individual drive
7. The selection of an electric motor is governed by
(a) nature of load to be handled
(b) environment conditions
(c) nature of electric supply available
(d) all of the above
8. Dc motor are still preferred for use in
(a) Electrical excavator, steel mills and cranes
(b) lathe and machine tools
(c) flour mills and jaw crushers
(d) paper industry
9. The least significant electrical characteristic in selection of electric motor flour mills is
(a) starting characteristics
(b) breaking
(C) running characteristics
(d) efficiency
10. The least significant feature while selecting a motor for centrifugal pumps is
(a) speed control
(b) power rating of motor
(c) operation speed
(d) starting characteristic
11. A typical active load
(a) hoist
(b) blower
( c) pump
( d) lathe
12. An elevator drive is required to operate in
(a) one quadrant
(b) two quadrant
(c) three quadrant
(d) four quadrant
13. Load torque constant at all speeds is represented by a
(a) fan
(b) compressor
(c) centrifugal pump load
14. The load for which the motor always starts on load is
(a) fan motor
(b) conveyor motor
(c) flour mill motor
(d) all of the above
15.Belt conveyor affer ...... starting torque
(a) high
(b) medium
(c) low
(d) zero
16. The travelling speed of a crane varies from
(a) 20 to 25m/s.
(b) 10 to 20 m/s.
(c) 1.0 to 2.5 m/s.
(d) 0.2 to 1.0 m/s.
17. The diameter of the motor shaft for an electric motor depends upon
(a) speed only
(b) power output
(c) speed and power output
(d) speed , power output and power factor
18. When an electric train is moving down hill , the dc motor will be operate as a dc
(a) series motor
(b) series generator
(c) shunt motor
(d) shunt generator
19. A dc series motor is used for an overhauling load. It can work stable if
(a) the armature is shunted by a resistor
(b) the field winding is reversed
(c) a resistor is put in series with the machine
(d) a divertor is put across the field
20.which motor should not be used for centrifugal pump
(a) series motor
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