A. trains
B. cranes
C. hoists
D. machine tools
Related Mcqs:
- If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens__________?
A. nothing will happen to the motor
B. this will make armature to take heavy current, possibly burning it
C. this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses D. motor will run at very slow speed - If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens____________?
A. this will make armature to take heavy current, possibly burning it
B. this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
C. nothing will happen to motor
D. motor will come to stop - In D.C. shunt motors as load is reduced__________________?
A. the speed will increase abruptly
B. the speed will increase in proportion to reduction in load
C. the speed will remain almost/constant
D. the speed will reduce - In case of D.C. shunt motors the speed is dependent on back e.m.f. only because____________?
A. back e.m.f. is equal to armature drop
B. armature drop is negligible
C. flux is proportional to armature current
D. flux is practically constant in D:C. shunt motors - In a D.C. shunt motor, speed is______________?
A. independent of armature current
B. directly proportional to the armature current
C. proportional to the square of the current
D. inversely proportional to the armature current - In a differentially compounded D.C. motor, if shunt field suddenly opens____________?
A. the motor will first stop and then run in opposite direction as series motor
B. the motor will work as series motor and run at slow speed in the same direction
C. the motor will work as series motor and run at high speed in the same direction
D. the motor will not work and come to stop - For a D.C. shunt motor if the excitation is changed_______________?
A. torque will remain constant
B. torque will change but power will remain constant
C. torque and power both will change
D. torque, power and speed, all will change - If the speed of a D.C. shunt motor is increased, the back e.m.f. of the motor will_________?
A. increase
B. decrease
C. remain same
D. become zero - The speed of a D.C. shunt motor is required to be more than full load speed. This is possible by______________?
A. reducing the field current
B. decreasing the armature current
C. increasing the armature current
D. increasing the excitation current
E. none of the above methods - If the field winding resistance of a DC shunt motor is increases, its speed will____________?
If the field winding resistance of a DC shunt motor is increases, its speed will
A. decreases
B. increases
C. remains same
D. none of the above
