1- The Eb/V ratio of a d.c. motor is an indication of its(c) Starting torque(b) Speed regulation2- The mechanical power developed by the armature of a d.e. motor is equal to(a) Efficiency(d) Running Torque(a) Armature current multiplied by back e.m.f. (b) Power input minus losses (c) Power outputmultiplied by efficiency(d) Power output plus iron losses3- In a d.c. motor, the mechanical output power actually comes from(a) Electrical input power (b) air-gap flux(c) Back e.m.f.(d) Field system4- Under constant load conditions, the speed of a d.c. motor is affected by(b) Field flux(c) Back e.m.f.(a) Armature current(d) Both (b) and (c)5- The shaft torque of a d.c. motor is less than its armature torque because of ... losses.(a) Copper(b) Rotational(c) Iron(d) Mechanical6- The Ta/la graph of a d.c. series motor is a(a) Parabola from no-load to overload(c) Parabola throughout(b) Parabola upto full-load and a straight line at overloads(d) Straight line throughout7- Which of the following d.c. motor would be suitable for drives requiring high starting torque but only fairlyconstant speed such as crushers?(a) Shunt(b) Series(c) Compound(d) Permanent magnet8- The current drawn by a 120 - V dc. motor of armature resistance 0.5 2 and back e.m.f. 110 V isampere.(a) 220(b) 240(c) 20(d) 5

In this question, We need to choose the correct options All are related to DC motor. as per our…

1- The Eb/V ratio of a d.c. motor is an indication of its (b) Speed regulation (c) Starting torque (a) Efficiency 2- The mechanical power developed by the armature of a d.e. motor is equal to (a) Armature current multiplied by back e.m.f. (b) Power input minus losses (c) Power output multiplied by efficiency (d) Running Torque (d) Power output plus iron losses 3- In a d.c. motor, the mechanical output power actually comes from (a) Electrical input power (b) air-gap flux (c) Back e.m.f. (d) Field system 4-Under constant load conditions the snee fade motor is affected by

1- The Eb/V ratio of a d.c. motor is an indication of its (b) Speed regulation (c) Starting torque (a) Efficiency 2- The mechanical power developed by the armature of a d.e. motor is equal to (a) Armature current multiplied by back e.m.f. (b) Power input minus losses (c) Power output multiplied by efficiency (d) Running Torque (d) Power output plus iron losses 3- In a d.c. motor, the mechanical output power actually comes from (a) Electrical input power (b) air-gap flux (c) Back e.m.f. (d) Field system 4-Under constant load conditions the snee fade motor is affected by

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter5: Resistors

Section: Chapter Questions

Problem 1PA

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