Description : The 'dielectric constant' of dry air or a vacuum is _______. A. 1 B. 10 C. 100 D. 1000
Last Answer : Answer: A
Description : The 'dielectric constant' is a numerical value indicating the effectiveness of a dielectric material in comparison to that of a standard, which is _______________. A. paper or cloth B. glass or mica C. plastic or Teflon D. dry air or a vacuum
Last Answer : Answer: D
Description : When shore power is being connected to a ship in dry dock, _____________. A. the ship's generators are paralleled with the shore power to provide continuous power B. proper phase sequence must be ... 450 volts must be supplied from the shore D. exactly 60 Hz must be provided by the terminal
Last Answer : Answer: B
Description : A megger is being used to test the insulation of an AC generator. The resistance value of a dry, clean winding will _____________. A. continue to rise as test potential is maintained, ... , becoming fairly steady after 5-7 minutes D. stabilize after approximately 2-4 minutes of fluctuation
Description : A 'dielectric' is a/an ________________. A. electrical insulator B. current flow C. good conductor D. semiconductor material
Description : If a cable of homogeneous insulation has a maximum stress of 10 kV/mm, then the dielectric strength of insulation should be (a) 5 kV/mm (b) 10 kV/mm (a) 15 kV/mm (d) 30 kV/mm
Last Answer : (b) 10 kV/mm
Description : Dielectric strength of rubber is around (a) 5 kV/mm (b) 15 kV/mm (c) 30 kV/mm (d) 200 kV/mm
Last Answer : (c) 30 kV/mm
Description : 63 The dielectric strength of transformer oil is expected to be A. 1kV B. 33kV C. 100kV D. 330 kV
Last Answer : B. 33kv
Description : The dielectric strength of transformer oil should be (A) 100 V. (B) 5 KV. (C) 30 KV. (D) 132 KV.
Last Answer : (C) 30 KV.
Description : Which of the following statements about copper wire sized by the AWG rating is correct? A. Number 12 AWG wire has a higher current rating than number 10 AWG wire. B. Number 10 AWG wire has a higher ... Number 12 AWG wire at 25°C has more resistance per 1000 feet than No. 10 AWG wire at 25°C.
Description : Which of the following statements concerning copper wire sized by AWG numbers is correct? A. Number 12 AWG wire has a higher current rating than 10 AWG wire. B. Number 12 AWG wire at 25°C has more ... dielectric strength than 12 AWG wire. D. Number 12 AWG wire is larger than number 10 AWG wire.
Description : Local action in a dry-cell, or lead-acid storage battery is the process whereby ________________. A. hydrogen gas is liberated B. the electrolyte compensates for overcharging C. potassium hydroxide ... carbon dioxide from the air D. the battery becomes discharged without being connected to a load
Description : The sparking voltage of the spark plug is A. 6 to 12 V B. 100 to 450 V C. 1 to 2 kV D. 20 to 30kV
Last Answer : ANSWER : D
Description : A three-phase alternator is operating at 450 volts, 250 amps at 0.6 power factor. If the power factor increases to 0.8, the kw load potential will increase by _____________. A. 38.525 kw B. 116.91 kw C. 155.88 kw D. 194.85 kw
Description : A three-phase alternator operates at 450 volts with a power factor of 0.8. If the ammeter indicates 250 amperes, what should be the KW meter reading? A. 90.00 KW B. 127.27 KW C. 155.70 KW D. 194.85 KW
Last Answer : Answer: C
Description : A three-phase alternator is developing 300 amps, with a 0.8 power factor, at 450 volts. The true indicated power on the kilowatt meter, located on the main switchboard, will be ____________. A. 133 kw B. 155 kw C. 187 kw D. 212 kw
Description : A three-phase alternator is operating at 450 volts with the switchboard ammeter indicating 300 amps. The kw meter currently indicates 163.6 KW, with a power factor of 0.7. If the power factor increases to 0.8, the KW meter would then read ____________. A. 181.4 KW B. 186.8 KW C. 194.2 KW D. 201.4 KW
Description : What is the load voltage 'Es' as shown in the illustration? EL-0083 A. 292 volts B. 360 volts C. 450 volts D. 810 volts
Description : If 450 volts AC were measured across the load as shown in the illustration it would indicate a/an _______________. EL-0083 A. open winding between 'H1' and 'X1' B. properly operating circuit C. open winding between 'X1' and 'X4' D. ground on one side of 'Ep'
Description : A three-phase alternator is operating at 450 volts with the switchboard ammeter indicating 300 amps. The kw meter currently indicates 163.6 KW, with a power factor of 0.7. If the power factor increases to 0.8, the KW meter reading would increase by ___ A. 17.8 KW B. 23.2 KW C. 30.6 KW D. 37.8 KW
Description : Why is the dielectric strength of vacuum infinite?
Last Answer : The dielectric strength of vacuum is infinite because there isno molecule in the vacuum.
Description : The amount of mechanical force or torque produced by an electric motor depends on the ________________. A. strength of its magnetic field B. amount of armature current flow C. length of conductor in the field D. all of the above
Description : Motor controllers are seldom troubled by grounds because ________________. A. cabinet heaters always keep internal components dry B. special insulation is used on wire for vital circuits C. ... on controller panels greatly reduce vibration D. contactors and relays are mounted on nonconducting panels
Description : What is the approximate voltage produced by a nickel-cadmium battery cell? A. 1.25 volts B. 1.50 volts C. 2.20 volts D. 6.05 volts
Description : Voltage can be stepped up from 6 to approximately a) 10,000 volts b) 15.00 0 volts c) 20,000 volts d) 25,000 volts
Last Answer : c) 20,000 volts
Description : How many volts is 13.8 kV?
Last Answer : 13,800 volts1 kv = 1 kilovolt = 1000 volts
Description : Convert 2.1 kV to volts.
Last Answer : 2100 volts.
Description : how can we express 0.40 kV in volts?
Last Answer : Kvx1000=400v
Description : If the illustrated device has a step-up ratio of 10 to 1 what voltage be measured at the secondary shortly after the primary of the device is connected to 110 volts DC with a current of 12 amps? EL-0055 A. 0 volts B. 110 volts C. 1000 volts D. 1100 volts
Description : When troubleshooting most electronic circuits, 'loading effect' can be minimized by using a voltmeter with a/an ___________________. A. input impedance much greater than the impedance across which the voltage ... sensitivity of less than 1000 ohms/volt D. sensitivity of more than 1000 volts/ohm
Description : A 4 pole lap wound dc shunt motor rotates at the speed of 1500 rpm, has a flux of 0.4 mWb and the total number of conductors are 1000. What is the value of emf? (A) 100 Volts. (B) 0.1 Volts. (C) 1 Volts. (D) 10 Volts.
Last Answer : Ans: D Given N = 1500 rpm, Φ = 0.4 mWb, Z = 1000, P = 4, & A= 4 Therefore, Eb = NΦPZ / 60 A = 1500 x 0.4 x 4 x 1000 x 10^-3 / 60 x 4 = 60/6 = 10 volts
Description : Emulsifier protection is associated with: a) Grounding protection b) Dielectric strength protection of cables and conductors c) Lightning protection d) Fire protection
Last Answer : Ans: D
Description : The removal of paint from electrical equipment, such as generators, should be cautiously undertaken because ____________. A. the mechanical shock of paint removal lessens the dielectric strength ... phase windings frequently become isolated from each other due to dust interference at the terminals
Description : Which of the listed conditions could indicate the need for cleaning electrical insulation? A. Low ambient temperature B. Low operating temperature C. High dielectric strength D. Low megger readings
Description : A megohmmeter is used to measure _____________. A. voltage B. dielectric strength C. current D. power
Description : When using a megohmmeter to test the dielectric strength of wire insulation, a continuous series of slight downscale kicks by the pointer is result of ____________. A. good insulation B. the ... dirty insulation C. the capacitance of the windings D. the dielectric-absorption effect of the insulation
Description : When a megohmmeter is used to test the dielectric strength of wire insulation, the initial dip of the pointer toward 'zero' is caused by _____________. A. good insulation B. the leakage of ... of dirty insulation C. the capacitance of the circuit D. the dielectric absorption effect of the insulation
Description : What is meant by Dielectric strength?
Last Answer : The maximum electrical potential gradient that a material can withstand without rupture usually specified in volts/millimeter of thickness. This also has known as electric strength.
Description : Electric field strength on a dust particle having charge equal to 8 × 10- 19 when plates are separated by distance of 2 cm and have a potential difference of 5 kV is A. 2.0 × 10-13 N B. 3 N C. 5 N D. 20 N
Last Answer : 2.0 × 10-13 N
Description : Three audio waves with 100,200 and 300 volts amplitude respectively, simultaneously modulate a 450 volts carrier. What is the total percent of modulation of the AM wave? A. 69 % B. 115.5 % C. 50% D. 83%
Last Answer : D. 83%
Description : Which of the listed pairs of materials make the best insulators? A. dry air and a vacuum B. tin and lead C. doped silicon and germanium D. paper and oil
Description : Which of the listed pairs of materials make the best insulators? A. copper and aluminum B. glass and mica C. dry air and a vacuum D. doped silicon and germanium
Description : Routine maintenance of dry-type transformers should include ____________. A. cleaning the windings, if accessible, with a vacuum cleaner or very low pressure air B. measuring and recording the winding ... . making sure that the units are close to bulkheads or corners to protect them from damage
Description : Compressed air should not be used to clean motor controller equipment because ________________. A. it may force metallic particles into coil insulation B. the surrounding area may need additional cleaning C. the air blast dries out insulation quickly D. a mask and respirator would be required
Description : The spacing between phase conductors of a 220 kV line is approximately equal to (a) 2 m (b) 3.5 m (c) 6 m (d) 8.5 m
Last Answer : (c) 6 m
Description : The dry-cell batteries, when connected as shown in the illustration, would produce ____________. EL-0070 A. 1.5 volts B. 2.5 volts C. 3.5 volts D. 4.5 volts
Description : Heating value of coal is approximately (A) 1000-2000 kcal / kg (B) 2000-4000 kcal / kg (C) 5000-6500 kcal / kg (D) 9000-10,500 kcal / kg
Last Answer : Ans: C
Description : While designing a stair, the product of rise and going is approximately kept equal to (A) 350 (B) 420 (C) 450 (D) 500
Last Answer : Answer: Option B
Description : On selling a fan at 8% loss and an iron box at 18% gain, a man gains rs.346.If he sells the fan at 7% gain and the iron box at 15% gain, then he gains rs.450. The actual price of the iron box is approximately?
Last Answer : Let the cost price of the fan be Rs X and Cost of the iron box beRs Y Then 18%Y – 8% X=346 ; That is 18Y-8X=34600 1 And 15%Y+8% X=450 ; that is 15Y+8X=450002 Solving 1 and 2 we get X=1102.275 Y=2412.12 therefore cost of ironbox is = 2412(approx.)