Discuss
menu
search
person
Login
Register
search
edit
Ask a Question
Discuss
All Activity
Q&A
Questions
Hot!
Unanswered
Tags
Ask a Question
The speed of a D.C. series motor is?
Speak Question
asked
Mar 20, 2018
by
anonymous
speed
series
motor
dc
thumb_up_alt
0
like
thumb_down_alt
0
dislike
71
views
Please
log in
or
register
to add a comment.
Please
log in
or
register
to answer this question.
1
Answer
Speak Answer
answered
Mar 20, 2018
by
anonymous
The speed of a D.C. series motor is
inversely proportional to the armature current.
thumb_up_alt
0
like
thumb_down_alt
0
dislike
Please
log in
or
register
to add a comment.
← Prev Question
Next Question →
Related questions
asked
Mar 20, 2018
by
anonymous
When two D.C. series motors are connected in parallel, the resultant speed is?
Last answer:
When two D.C. series motors are connected in parallel, the resultant speed is normal speed.
dc
series
motors
speed
thumb_up_alt
0
like
thumb_down_alt
0
dislike
305
views
1
answer
asked
Mar 20, 2018
by
anonymous
In a D.C. shunt motor, speed is?
Last answer:
In a D.C. shunt motor, speed is independent of armature current.
dc
shunt
motor
speed
thumb_up_alt
0
like
thumb_down_alt
0
dislike
62
views
1
answer
asked
Mar 20, 2018
by
anonymous
In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to?
Last answer:
In a D.C. series motor, if the armature current is reduced by 50%, the torque of the motor will be equal to 25% of the previous value.
dc
motor
series
thumb_up_alt
0
like
thumb_down_alt
0
dislike
142
views
1
answer
asked
Mar 20, 2018
by
anonymous
The speed of a D.C. motor can be controlled by varying
The speed of a D.C. motor can be controlled by varying 1. Its flux per pole 2. Resistance of armature circuit 3. Applied voltage 4. All of the above
Last answer:
The speed of a D.C. motor can be controlled by varying 1. Its flux per pole 2. Resistance of armature circuit 3. Applied voltage 4. All of the above
speed
dc
motor
varying
thumb_up_alt
0
like
thumb_down_alt
0
dislike
115
views
1
answer
asked
Mar 20, 2018
by
anonymous
The speed of a D.C. shunt motor can be increased by?
Last answer:
The speed of a D.C. shunt motor can be increased by increasing the resistance in field circuit.
speed
dc
shunt
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
88
views
1
answer
asked
Mar 20, 2018
by
anonymous
A D.C. series motor is that which?
Last answer:
A D.C. series motor is that which has its field winding consisting of thick wire and less turns.
dc
series
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
51
views
1
answer
asked
Mar 20, 2018
by
anonymous
If a D.C. series motor is operated on A.C. supply, it will?
Last answer:
If a D.C. series motor is operated on A.C. supply, it will spark excessively, have poor efficiency, have poor power factor.
dc
series
motor
operated
ac
supply
thumb_up_alt
0
like
thumb_down_alt
0
dislike
63
views
1
answer
asked
Mar 20, 2018
by
anonymous
The direction of rotation of a D.C. series motor can be changed by?
Last answer:
The direction of rotation of a D.C. series motor can be changed by interchanging field terminals.
direction
rotation
dc
series
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
75
views
1
answer
asked
Mar 20, 2018
by
anonymous
As the load is increased the speed of D.C. shunt motor will?
Last answer:
As the load is increased the speed of D.C. shunt motor will reduce slightly.
load
increased
speed
dc
shunt
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
106
views
1
answer
asked
Mar 20, 2018
by
anonymous
A.C. series motor as compared to D.C. series motor has?
Last answer:
A.C. series motor as compared to D.C. series motor has smaller brush width, less number of field turns, more number of armature turns, less air gap.
ac
series
motor
compared
dc
thumb_up_alt
0
like
thumb_down_alt
0
dislike
69
views
1
answer
asked
Mar 20, 2018
by
anonymous
If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will?
Last answer:
If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will increase.
speed
dc
shunt
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
111
views
1
answer
asked
Mar 20, 2018
by
anonymous
When a D.C. series motor is connected to A.C. supply, the power factor will be low because of?
Last answer:
When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.
dc
series
motor
the
power
factor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
92
views
1
answer
asked
May 8, 2018
by
anonymous
A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s.
A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be
Last answer:
A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be 474 V
dc
shunt
motor
rated
load
speed
thumb_up_alt
0
like
thumb_down_alt
0
dislike
225
views
1
answer
asked
Apr 29, 2018
by
anonymous
In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at
In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at half full load in N -m is :
Last answer:
In a 2 kW, 200 V, 1000 rpm. DC series motor the torque at full load was found to be 0.3 N -m. The torque at half full load in N -m is : 0.075
dc
series
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
70
views
1
answer
asked
Dec 16, 2017
by
anonymous
What are the speed control methods of dc motor?
What are the speed control methods of dc motor?
Last answer:
Field control of DC motor Armature control of DC motor
speed
control
methods
dc
motor
thumb_up_alt
3
like
thumb_down_alt
0
dislike
150
views
2
answers
asked
Sep 18, 2018
by
anonymous
Describe the reason of using dc series motor for electric trains.
Describe the reason of using dc series motor for electric trains.
Last answer:
Electric trains require an inverse torque speed characteristics for proper operation. That is a higher torque is required at start (when speed is nil or low) and as the train picks up ... torque - speed characteristics of DC series motors match, these motors are suitable for electric trains
dc
series
motor
electric
trains
thumb_up_alt
0
like
thumb_down_alt
0
dislike
114
views
1
answer
asked
Mar 20, 2018
by
anonymous
Speed torque characteristic of a repulsion induction motor is similar to that of a D.C.?
Last answer:
Speed torque characteristic of a repulsion induction motor is similar to that of a D.C. compound motor.
speed
torque
characteristic
repulsion
induction
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
69
views
1
answer
asked
Jul 5, 2019
by
anonymous
Why does the speed of a DC shunt motor decrease as the load increases?
Why does the speed of a DC shunt motor decrease as the load increases?
Last answer:
Because if the load is increasing then the torque must also be increase. If not then the speed of motor will decrease.
why
does
the
speed
of
a
dc
shunt
motor
decrease
as
load
increases
thumb_up_alt
0
like
thumb_down_alt
0
dislike
2.6k
views
1
answer
asked
Apr 28, 2018
by
anonymous
The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a
The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ (A) directly proportional to α and Φ (B) inversely proportional to α and Φ (C) directly proportional to α and inversely proportional to Φ (D) directly proportional to Φ and inversely proportional to α
Last answer:
The no-load speed of a single-phase SCR bridge converter fed separately excited dc motor operating at a firing delay angle, α and flux, Φ directly proportional to α and inversely proportional to Φ
no-load
speed
single-phase
scr
bridge
converter
fed
separately
excited
dc
motor
operating
thumb_up_alt
0
like
thumb_down_alt
0
dislike
122
views
1
answer
asked
Mar 15, 2018
by
anonymous
Why a dc series motor has a high starting torque?
Why a dc series motor has a high starting torque?
dc
series
motor
high
starting
torque
thumb_up_alt
0
like
thumb_down_alt
0
dislike
64
views
0
answers
asked
May 7, 2020
by
anonymous
State the modification to be done in dc series motor to work satisfactorily as ac series motor. State applications of ac series motor.
State the modification to be done in dc series motor to work satisfactorily as ac series motor. State applications of ac series motor.
Last answer:
Modifications are necessary in a dc series motor so that it operates satisfactorily on ac supply. The modifications are as follows: 1) AC series motor is built with a few field turns as ... and grinders 5) High speed vacuum cleaners 6) Sewing machines 7) Food processors 8) Drilling machine
state
the
modification
to
be
done
in
dc
series
motor
work
satisfactorily
as
ac
applications
of
thumb_up_alt
0
like
thumb_down_alt
0
dislike
79
views
1
answer
asked
Mar 15, 2018
by
anonymous
What are the advantages of DC series motor?
What are the advantages of DC series motor?
advantages
dc
series
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
80
views
0
answers
asked
Apr 21, 2020
by
anonymous
Brake test on DC series motor
Brake test on DC series motor
Last answer:
.embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
brake
test
on
dc
series
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
159
views
2
answers
asked
Mar 15, 2018
by
anonymous
Why dc series motor should not be started at no load?
Why dc series motor should not be started at no load?
dc
series
motor
started
load
thumb_up_alt
0
like
thumb_down_alt
0
dislike
597
views
0
answers
asked
Mar 20, 2018
by
anonymous
In case of D.C. shunt motors the speed is dependent on back e.m.f. only because?
Last answer:
In case of D.C. shunt motors the speed is dependent on back e.m.f. only because flux is practically constant in D:C. shunt motors.
dc
shunt
motors
speed
back
emf
thumb_up_alt
0
like
thumb_down_alt
0
dislike
146
views
1
answer
asked
Mar 20, 2018
by
anonymous
In case of conductively compensated D.C. series motors, the compensating winding is provided?
Last answer:
In case of conductively compensated D.C. series motors, the compensating winding is provided in series with armature winding.
dc
motors
series
thumb_up_alt
0
like
thumb_down_alt
0
dislike
71
views
1
answer
asked
Mar 20, 2018
by
anonymous
In a A.C. series motor armature coils are usually connected to commutator?
Last answer:
In a A.C. series motor armature coils are usually connected to commutator through resistance.
ac
series
motor
armature
coils
usually
commutator
thumb_up_alt
0
like
thumb_down_alt
0
dislike
87
views
1
answer
asked
Mar 20, 2018
by
anonymous
In case the back e.m.f. and the speed of a D.C. motor are doubled, the torque developed by the motor will?
Last answer:
In case the back e.m.f. and the speed of a D.C. motor are doubled, the torque developed by the motor will remain unchanged.
dc
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
148
views
1
answer
asked
Mar 20, 2018
by
anonymous
The speed of a D.C. shunt motor more than its full-load speed can be obtained by?
Last answer:
The speed of a D.C. shunt motor more than its full-load speed can be obtained by decreasing the field current.
dc
shunt
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
91
views
1
answer
asked
May 1, 2018
by
anonymous
The speed of a three-phase induction motor is controlled by variable voltage variable frequency control
The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque (1) Decreases (2) Increases (3) Remains constant (4) None of the above
Last answer:
The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque Increases
speed
three-phase
induction
motor
controlled
variable
voltage
frequency
control
thumb_up_alt
0
like
thumb_down_alt
0
dislike
118
views
1
answer
asked
Mar 20, 2018
by
anonymous
The speed of a universal motor is usually reduced by using?
Last answer:
The speed of a universal motor is usually reduced by using gearing.
speed
universal
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
78
views
1
answer
asked
Mar 20, 2018
by
anonymous
In case of a reluctance motor, when the load is increased so that it cannot maintain synchronous speed the motor will?
Last answer:
In case of a reluctance motor, when the load is increased so that it cannot maintain synchronous speed the motor will run as induction motor.
reluctance
motor
synchronous
speed
thumb_up_alt
0
like
thumb_down_alt
0
dislike
87
views
1
answer
asked
Mar 20, 2018
by
anonymous
The speed/load characteristics of a universal motor is same as that of?
Last answer:
The speed/load characteristics of a universal motor is same as that of D.C. series motor.
speed
load
characteristics
universal
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
69
views
1
answer
asked
Mar 20, 2018
by
anonymous
Speed control of a universal motor is achieved by?
Last answer:
Speed control of a universal motor is achieved by varying field flux with tapped field windings, connecting rheostat in series, applying variable voltage by means of silicon controlled rectifier, applying variable voltage by means of variable auto-transformer.
speed
control
universal
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
77
views
1
answer
asked
Apr 28, 2018
by
anonymous
The speed of a 2-pole, 3-phase stepper motor operated by 1200 pulses/min
The speed of a 2-pole, 3-phase stepper motor operated by 1200 pulses/min (A) 100 rpm (B) 200 rpm (C) 400 rpm (D) 800 rpm
Last answer:
The speed of a 2-pole, 3-phase stepper motor operated by 1200 pulses/min 200 rpm
speed
2-pole
3-phase
stepper
motor
operated
thumb_up_alt
0
like
thumb_down_alt
0
dislike
121
views
1
answer
asked
Apr 27, 2020
by
anonymous
Write two applications of D.C. series motor.
Write two applications of D.C. series motor.
Last answer:
The applications of D.C. series motor: 1. Cranes 2. Hoists 3. Trolley and cars 4. Conveyors 5. For traction work i.e. electric locomotives 6. Elevator 7. Air compressor
write
two
applications
of
d
c
series
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
58
views
1
answer
asked
Mar 20, 2018
by
anonymous
The speed control of universal motor used for sewing machines is by?
Last answer:
The speed control of universal motor used for sewing machines is by varying the resistance.
speed
control
universal
motor
used
sewing
machines
thumb_up_alt
0
like
thumb_down_alt
0
dislike
70
views
1
answer
asked
Mar 15, 2018
by
anonymous
Why the speed of synchronous motor is constant?
Why the speed of synchronous motor is constant?
speed
synchronous
motor
constant
thumb_up_alt
0
like
thumb_down_alt
1
dislike
54
views
0
answers
asked
Mar 20, 2018
by
anonymous
Centrifugal switch disconnects the auxiliary winding of the motor at about what percent of synchronous speed?
Last answer:
Centrifugal switch disconnects the auxiliary winding of the motor at about 70 to 80 percent of synchronous speed.
centrifugal
switch
disconnects
auxiliary
winding
motor
synchronous
speed
thumb_up_alt
0
like
thumb_down_alt
0
dislike
139
views
1
answer
asked
Mar 20, 2018
by
anonymous
If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in?
Last answer:
If the centrifugal switch does not open at 70 to 80 percent of synchronous speed of motor, it would result in damage to the starting winding.
synchronous
speed
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
69
views
1
answer
asked
Aug 9, 2017
by
anonymous
speed control methods of three phase induction motor?
speed control methods of three phase induction motor?
Last answer:
Speed control of three phase induction motor
speed
control
phase
induction
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
197
views
2
answers
asked
Mar 20, 2018
by
anonymous
Which motor has the poorest speed control?
Last answer:
Series motor has the poorest speed control.
motor
poorest
speed
control
thumb_up_alt
0
like
thumb_down_alt
0
dislike
79
views
1
answer
asked
Mar 20, 2018
by
anonymous
For the same H.P. rating and full load speed, following motor has poor starting torque?
Last answer:
For the same H.P. rating and full load speed, following motor has poor starting torque differentially compounded.
hp
rating
full
load
speed
motor
poor
starting
torque
thumb_up_alt
0
like
thumb_down_alt
0
dislike
115
views
1
answer
asked
Mar 20, 2018
by
anonymous
In variable speed motor?
Last answer:
In variable speed motor a weaker commutating field is needed at low speed than at high speed.
variable
speed
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
45
views
1
answer
asked
Mar 20, 2018
by
anonymous
In A.C. series motor compensating winding is employed to?
Last answer:
In A.C. series motor compensating winding is employed to reduce sparking at the brushes.
ac
series
motor
compensating
winding
employed
thumb_up_alt
0
like
thumb_down_alt
0
dislike
96
views
1
answer
asked
Mar 20, 2018
by
anonymous
At the instant of starting when a D.C. motor is put on supply, it behaves like?
Last answer:
At the instant of starting when a D.C. motor is put on supply, it behaves like a low resistance circuit.
dc
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
65
views
1
answer
asked
Mar 20, 2018
by
anonymous
As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent...
As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit?
Last answer:
As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit a resistance is connected in series with armature.
dc
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
115
views
1
answer
asked
Mar 20, 2018
by
anonymous
The starting resistance of a D.C. motor is generally?
Last answer:
The starting resistance of a D.C. motor is generally low.
starting
resistance
dc
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
76
views
1
answer
asked
Mar 20, 2018
by
anonymous
By looking at which part of the motor, it can be easily confirmed that a particular motor is D.C. motor?
Last answer:
By looking at Commutator part of the motor, it can be easily confirmed that a particular motor is D.C. motor.
motor
dc
thumb_up_alt
0
like
thumb_down_alt
0
dislike
79
views
1
answer
asked
Mar 20, 2018
by
anonymous
If the field of a D.C. shunt motor gets opened while motor is running?
Last answer:
If the field of a D.C. shunt motor gets opened while motor is running the motor will attain dangerously high speed.
field
dc
shunt
motor
thumb_up_alt
0
like
thumb_down_alt
0
dislike
94
views
1
answer
...