Quiz: Electrical Engineering
Exam: UPSSSC JE
Topic: DC Generator
Each question carries 1 mark.
Negative marking: 1/4 mark
Time: 10 Minute
Q1. The voltmeter connected across a generator reads voltage same at no load and at full load (rated). The generator is of type
(a) shunt generator
(b) series generator
(c) Level compound
(d) Short-shunt compound
Q2. The residual magnetism of a dc shunt generator can be regained by
(a) connecting the shunt field to a battery
(b) running the generator on no load for some time
(c) ground the shunt field
(d) reversing the direction of rotation of the generator
Q3. Flashing of field of dc generator means
(a) neutralization of residual magnetism
(b) creation of residual magnetism by a dc source
(c) increasing flux density by providing extra ampere-turns in field
(d) none of the above
Q4. A dc series generator is employed
(a) as a booster to maintain constant voltage at the load end of the feeder.
(b)for supplying traction load
(c) for supplying industrial load at constant voltage
(d) for battery charging
Q5. The type of dc generator used for arc welding purpose is a
(a) series generator
(b) shunt generator
(c) cumulatively compound generator
(d) differentially compound generator
Q6. When two dc series generator are operating in parallel, an equalizer bar is used
(a) to reduce armature reaction
(b) to increase emf
(c) to increase the speed
(d) so that the two similar machines take approximately equal load current
Q7. The simplest way of shifting load from one shunt generator to the other operating in parallel is by
(a) adjustment of speed
(b) adjustment of armature resistance
(c) adjustment of field rheostats
(d) using equalizer connections
Q8. If field of one of two generators operating in parallel is made very weak, then it will
(a) not take any load
(b) take major share of load
(c) operate as a motor and run in the same direction
(d) operate as a motor and run in the opposite direction
Q9. For parallel operation, the dc generators generally preferred are
(a) shunt
(b) series
(c) under compound
(d) Both (a) and (c)
Q10. The output of any electrical motor is taken from the
(a) armature
(b) field
(c) coupling mounted on shaft
(d) motor frame
Solutions
S1. Ans. (c)
Sol. Level compound
S2. Ans. (a)
Sol. connecting the shunt field to a battery
S3. Ans. (b)
Sol. creation of residual magnetism by a dc source
S4. Ans. (a)
Sol. as a booster to maintain constant voltage at the load end of the feeder
S5. Ans. (d)
Sol. differentially compound generator
S6. Ans. (d)
Sol. so that the two similar machines take approximately equal load current
S7. Ans. (c)
Sol. adjustment of field rheostats
S8. Ans. (c)
Sol. operate as a motor and run in the same direction
S9. Ans. (d)
Sol. Both shunt and under compound
S10. Ans. (c)
Sol. coupling mounted on shaft
