Description : Which of the following are the parts of a DC generator that convert the AC in the armature to DC in the external circuit. Are these parts the: w) field poles x) slip rings and the brushes y) commutator and the brushes z) armature and the core
Last Answer : ANSWER: Y -- COMMUTATOR AND THE BRUSHES
Description : A synchro has (A) a 3-phase winding on rotor and a single-phase winding on stator. (B) a 3-phase winding on stator and a commutator winding on rotor. (C) a 3-phase winding on stator and a single-phase winding on rotor. (D) a single-phase winding on stator and a commutator winding on rotor.
Last Answer : Ans: C Synchros : The basic synchro unit called a synchro transmitter. It’s construction similar to that of a Three phase alternator.
Description : A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an _____________. A. rotor B. stator C. exciter D. armature
Last Answer : Answer: C
Description : In the illustrated device, the part labeled '1A' _________. EL-0001 A. are start and run windings for a single phase shaded pole induction motor B. is the stator for a polyphase induction ... armature for a squirrel cage rotor motor D. are direct current shunt field windings for a universal motor
Last Answer : Answer: B
Description : In an induction motor, rotor currents are circulated in the rotor by _____________. A. slip rings and brushes B. an armature and brushes C. inductive reaction of the rotating stator field D. external variable resistors
Description : A color television set employs a 25,000 volt electron accelerator to produce the picture and potentially harmful radiation which must be shielded against. The main component of this radiation consists ... which penetrate the picture tube x) soft x-rays y) microwaves z) ultraviolet radiation
Last Answer : ANSWER: X -- SOFT X-RAYS
Description : The function of the commutator in a DC motor is to ________. A. reverse the flow of current through the armature B. reverse the flow of current in the field poles C. reduce the reluctance of the magnetic path through the motor D. shift the neutral running plane of the brushes to prevent sparking
Last Answer : Answer: A
Description : State the function of following parts of DC motor : i) Yoke ii) Poles iii) Field winding iv) Commutator.
Last Answer : Function : i) Yoke: The yoke serves the following two purposes. i) It supports the other components such as poles and provides mechanical protection for whole machine. ii) It forms a part of ... one pole to another and thus to help the motor to develop a continuous and unidirectional torque
Description : Liquid fuels can be used to generate electricity in a variety of ways. Which of the following technologies converts liquid fuel directly to electricity without a combustion step? w) turbine x) battery y) fuel cell z) Stirling engine
Last Answer : ANSWER: Y -- FUEL CELL
Description : You use a hydrometer to check the condition of the electrolyte in your car battery. It is actually measuring what property of the fluid? w) charge x) density y) temperature z) surface tension
Last Answer : ANSWER: X -- DENSITY
Description : A synchronous motor maintains synchronism with the rotating field because _____________. A. field strength varies directly with rotor slip B. DC current applied to the rotor coils causes the rotor ... the flux created by the excitation current D. the stator flux rotates in the opposite direction
Description : To reverse the direction of rotation of a three-phase AC induction motor, do one of the following: w) reverse any two of the three-phase connections x) change the frequency of the applied AC power y) operate the motor below the stall torque at very high slip z) none of the above
Last Answer : ANSWER: W -- REVERSE ANY TWO OF THE THREE-PHASE CONNECTIONS
Description : Which of the following components are used to convert alternating current produced in the generator windings to direct current? A. Armature and equalizer B. Commutator and brushes C. Rotor and interpoles D. Field and exciter
Description : Deforestation is not a major environmental problem in w) the Amazon x) Borneo y) Oregon z) West Germany
Last Answer : ANSWER: Z -- WEST GERMANY
Description : Which of the following is not a major pollutant from automobiles. w) carbon monoxide x) unburned hydrocarbons y) nitrous oxide z) sulfur dioxide
Last Answer : ANSWER: Z -- SULFUR DIOXIDE
Description : What is the major visible constituent of the exhaust plume from a natural gas-fired power plant? w) carbon dioxide x) carbon monoxide y) smoke z) water
Last Answer : ANSWER: Z -- WATER
Description : The speed of a squirrel-cage induction motor is determined by the ____________. A. diameter of the stator B. number of stator poles C. rotor winding resistance D. rotor conducting bars resistance
Description : The speed of a three-phase squirrel-cage induction-type motor operating in a fixed frequency system is varied by changing the _____________. A. number of phases to the motor B. number of stator poles C. locked rotor current D. resistance of the rotor winding
Description : The speed of a squirrel cage induction motor is determined by the _____________. A. diameter of the stator B. number of stator poles C. rotor winding resistance D. bar resistance of the conducting rotor
Description : A three phase slip ring induction motor is fed from the rotor side with stator winding short circuited stator is: (1) Slip frequency (2) Supply frequency (3) Frequency corresponding to rotor speed (4) Zero
Last Answer : A three phase slip ring induction motor is fed from the rotor side with stator winding short circuited stator is: Slip frequency
Description : The purpose of a cage rotor winding placed on the rotor of a synchronous motor is to _____________. A. provide excitation to the DC field B. start the machine as an induction motor C. contribute extra torque at synchronous speed D. prevent the machine from falling out of step
Description : An open in the armature of a DC motor is suspected, but is not found by visual inspection of the commutator. The next step in troubleshooting this problem is to ________________. A. conduct a ... windings C. conduct an insulation resistance test of the armature D. test the commutator for a ground
Description : A flickering ground detection lamp on a DC system would indicate a _____________. A. multiple-ground condition in the distribution system B. ground in an armature coil of an operating machine C. ground in a motor accompanied with a short D. short between two adjacent bars of the generator commutator
Description : A shunt-wound DC generator is one in which the shunt field windings are in parallel with the _____________. A. commutator B. brushes C. armature D. all of the above
Last Answer : Answer: D
Description : The purpose of the commutator and brushes on a DC generator is to _____________. A. transfer generated direct current voltage from the armature to the line B. convert the alternating voltage ... contact method to excite the field D. reduce sparking between the armature and the carbon brushes
Description : A commutator in a d.c. machine (A) Reduces power loss in armature. (B) Reduces power loss in field circuit. (C) Converts the induced a.c armature voltage into direct voltage. (D) Is not necessary.
Last Answer : Ans: C As name suggests, it commutes ac into dc.
Description : The most suitable motor oil for use in a car in cold weather is: w) a high viscosity oil x) a low viscosity oil y) a medium viscosity oil
Last Answer : ANSWER: X -- A LOW VISCOSITY OIL
Description : Evaporation from water surfaces exposed to air is not dependent of the: w) velocity of the wind x) humidity y) temperature z) depth of the water
Last Answer : ANSWER: Z -- DEPTH OF THE WATER
Description : Dante is the name of an eight-legged robot designed to repel into the crater of Erebus. This volcano is located in w) Italy x) the Hawaiian chain y) Antarctica z) Japan
Last Answer : ANSWER: Y -- ANTARCTICA
Description : Who is known as the Father of the Atomic Bomb? w) Albert Einstein x) J. Robert Oppenheimer y) General Leslie Groves z) Edward Teller
Last Answer : ANSWER: X -- J. ROBERT OPPENHEIMER
Description : In 1991, the frozen body of a late stone age man was found amazingly intact in the Alps near the Italian-Austrian border. Its age was determined to be about: w) 2,200 years x) 5,300 years y) 12,800 years z) 30,000 years
Last Answer : ANSWER: X -- 5,300 YEARS
Description : The sun makes up approximately what percent of matter in our solar system? w) 17% x) 50% y) 85% z) 99%
Last Answer : ANSWER: Z -- 99%
Description : Who was the first scientist credited with pointing out that certain gases could cause a greenhouse effect? w) John Tyndall x) Charles Darwin y) Roger Tory Peterson z) Stephen Jay Gould
Last Answer : ANSWER: W -- JOHN TYNDALL
Description : What range of frequencies are usually referred to as the Ultra High Frequency (UHF) Band? w) 3 to 30 Mega Hertz x) 30 to 300 Mega Hertz y) 300 to 3,000 Mega Hertz z) 30,000 to 300,000 Mega Hertz
Last Answer : ANSWER: Y -- 300 to 3,000 MEGA HERTZ
Description : Which of the following is considered a renewable resource? w) Coal fired power plant x) Hydroelectric dam y) Combustion turbine facility z) Nuclear fission power plant
Last Answer : ANSWER: X -- HYDROELECTRIC DAM
Description : The U.S. EPA recently concluded that environmental tobacco smoke should be considered (quote) w) "a possible human teratogen" x) "a priority air pollutant" y) "a known human carcinogen" z) "a possible human carcinogen"
Last Answer : ANSWER: Y -- A KNOWN HUMAN CARCINOGEN
Description : TCDD (2,3,6,7-tetrachlorodibenzo(p)dioxin) is a toxic synthetic chemical. The most consistent adverse effect observed in exposed humans is: w) liver cancer x) birth defects y) disfiguring skin eruption z) an exaggerated sense of well-being
Last Answer : ANSWER: Y -- DISFIGURING SKIN ERUPTION (CHLORACNE)
Description : Compared to terrestrial environments, aquatic environments are more stable in: w) temperature range x) producer consumer distribution y) sunlight absorbed z) number species
Last Answer : ANSWER: W -- TEMPERATURE RANGE
Description : Approximately what percentage of the electricity produced in the United States is consumed by residential appliances? w) 20% x) 33% y) 50% z) 66%
Last Answer : ANSWER: X -- 33%
Description : A radio station is broadcasting at 3750 khz (kilohertz). This station would be found in which radio band? w) 20 meter x) 40 meter y) 80 meter z) 160 meter
Last Answer : ANSWER: Y -- 80 METER
Description : A homeowner replaces a 65 watt incandescent bulb with a 15 watt compact fluorescent lamp. The light is on 2000 hours a year. If electricity cost 10 cents a kilowatt-hour, how much money is saved on the electric bill in one year? w) $50.00 x) $10.00 y) $5.00 z) $1.00
Last Answer : ANSWER: X -- $10.00
Description : Which of the following people is credited as being the father of mass production? w) Thomas Edison x) Otto Graham y) Henry Ford z) Eli Whitney
Last Answer : ANSWER: Z -- ELI WHITNEY
Description : In daylight the human eye is most sensitive to which color? w) Green x) Red y) Blue z) Orange
Last Answer : ANSWER: W -- GREEN
Description : One trillion is 1 followed by 12 zeros. What is 1 followed by 18 zeros? w) 1 quadrillion x) 1 quintillion y) 1 septillion z) 1 octillion
Last Answer : ANSWER: X -- 1 QUINTILLION
Description : In the Tyndall Effect, the intensity of scattered radiation is inversely proportional to the fourth power of the wavelength. Which one of the following colors of light would exhibit the most intense Tyndall scattering? w) yellow x) green y) orange z) violet
Last Answer : ANSWER: Z -- VIOLET
Description : What form of radiation most closely resembles X-rays? w) alpha x) beta y) gamma z) neutron
Last Answer : ANSWER: Y -- GAMMA
Description : What is the approximate weight in pounds of the atmosphere on a 1 sq. ft. surface at sea level? w) 15 lbs. x) 1500 lbs. y) 2100 lbs. z) 20,000 lbs.
Last Answer : ANSWER: Y -- 2100 LBS.
Description : In a precise diet and nutrition study, you need to determine the average weight and average height of a group each to a precision of 1%. The minimum sample size required is w) 10 x) 100 y) 1000 z) 10,000
Last Answer : ANSWER: Z -- 10,000
Description : The heat exhaust of an automobile with an internal combustion engine represents approximately what percent of the energy of the original fuel? w) 10 % x) 50 % y) 35 % z) 5 %
Last Answer : ANSWER: Y -- 35 %
Description : The most abundant organic molecule on the surface of the Earth is: w) cellulose x) chitin y) DNA z) hemoglobin
Last Answer : ANSWER: W -- CELLULOSE