1. In Lap winding, the number of brushes is always: a. Double the number of poles b. Same as number of poles e. Half the number of poles d. Multiple of number of poles 2.The material for commutator Brushes is generally: a. Cast Iron 3. The essential condition for parallel operation of two D.C. generators is that they have: a. Same kW rating b. The same operation r.p.m. e. The same drooping voltage characteristics d. Same percentage regulation 4. Magnetic field in a D.C. generator is produced by a. Electromagnets b. Permanent magnets e. Both (a) and (b) d. None of the above 5. In case of D.C. machines, mechanical losses are primary function of a. Current b. Voltage e. Speed d. None of above b. Copper e. Carbon d. Mica

1. In Lap winding, the number of brushes is always: a. Double the number of poles b. Same as number of poles e. Half the number of poles d. Multiple of number of poles 2.The material for commutator Brushes is generally: a. Cast Iron 3. The essential condition for parallel operation of two D.C. generators is that they have: a. Same kW rating b. The same operation r.p.m. e. The same drooping voltage characteristics d. Same percentage regulation 4. Magnetic field in a D.C. generator is produced by a. Electromagnets b. Permanent magnets e. Both (a) and (b) d. None of the above 5. In case of D.C. machines, mechanical losses are primary function of a. Current b. Voltage e. Speed d. None of above b. Copper e. Carbon d. Mica

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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14. A shunt generator has a no-load terminal voltage of 270 and a voltage of 245 when it delivers 180 amp. Assume a straight-line characteristic and determine the voltage when the current is 120 amp. What is the equivalent load resistance under this condition?
A 220V shunt generator has an armature resistance of 0.02ohms and a shunt field resistance of 44ohms. at rate load, the driving engine develops 62.26hp. If the iron and friction losses amount to 1600W, how much is the current delivered to the load at this condition? (Our subject is ELECTRICAL MACHINE 1, and our lesson is Losses and Efficiency on the DC MACHINE) (I need a clean solution ma'am/sir. Thank you do much)
A shunt generator has a no-load terminal voltage of 270 and a voltage of 245 when it delivers 180 amp. Assume a straight-line characteristic and determine the following: the voltage when the current is 120 amp and What is the equivalent load resistance under this condition?
Write a technical manual of that will inform others of the efficiency and inefficiency of all types of motor and generator (ac and dc). Explore how any apparent inefficiencies could be improved. Show examples of these machines and using suitable examples, point out the areas of inefficiency (if applicable) and where and how things can be improved. Then provide the solution to the following as an example in your report. A 2-pole, single-phase alternator driven at 3000rpm require a mechanical input to its rotor of 30kW when it is delivering its full-load output of 30kW. Under this condition the fixed and variable losses are1100W and 2.8kW respectively, and the rotor field winding is supplied from a 110V dc source. Given that the full-load efficiency is 87%, determine. i) the frequency generated, ii) the input driving torque on full-load and iii) the rotor field current
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a 220V shunt generator has an armature resistance of 0.02ohms and a shunt field resistance of 44 ohms. at rate load, the driving engine develops 62.26 hp. If the iron and friction losses amount to 1600W, how much is the current delivered to the load at this condition? (Our subject is ELECTRICAL MACHINE 1, and our lesson is Losses an Efficiency in DC Machine) (I need clean solution ma'am/sir, thank you so much)
A long shunt compound dc generator delivers a load current of 69 A at 396 V and has armature, series field and shunt field resistances of 0.096 Ω, 0.014 Ω, and 259 Ω, respectively. Calculate the armature current in ampere.
A long shunt compound dc generator delivers a load current of 78 A at 466 V and has armature, series field and shunt field resistances of 0.077 Ω, 0.04 Ω, and 290 Ω, respectively. Calculate the armature current in ampere (up to four decimal places).
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Here it is the equivalent circuit of and induction motor and it is per phase circuit my question is name for me the variable for example R1 is the winding resistance and so an the all variable and please show me a pic of the real machine with the variable for example for R1 happens because of the winding i need to see the winding in the real machine, please help me to understand well