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单选题
When the current in a power transmission line is increased, the power loss （）
A
increases as the square of the current
B
decreases as the square root of the current
C
remains the same, as it is independent of current flow
D
increases in direct proportion as the current
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单选题（）conveys a signal of desired rudder angle from the bridge and activates the power unit and transmission system unit the desired angle is reached.A
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单选题Which of the following can be used to insert a new line below the current line inside a vi session?（）A
oB
aC
pD
A
考题
单选题When voltage and current developed in an AC circuit reach their peak values at the same time, the power factor is （）A
laggingB
leadingC
maximumD
minimum
考题
单选题When you are making a high potential test on a piece of repaired electrical machinery, a rise in leakage current indicates （）.A
good insulationB
bad insulationC
high insulation power factorD
a high slot discharge factor
考题
单选题The transmission system transmitting power from the engine to the propeller is composed of shafts, bearings, and（）A
propellerB
flying wheelC
main engineD
crankshaft
考题
单选题When landing a lifeboat through heavy surf with a strong current running parallel to the beach (from right to left when facing from seaward) the recommended procedure is to（）.A
approach while coming to the left to take advantage of the currentB
drop an anchor outside the surf line，then pay out anchor line over the bow while the seas carry the boat toward the beachC
approach slow enough so that the boat can be brought around to meet breaking seas on the bowD
rig a drogue with tripping line over the bow，back ashore with drogue tripped between breakers
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单选题When measuring AC current flow, you must always connect the meter （）A
in series with the power source and loadB
in parallel with the power source and loadC
insuring correct polarityD
using the lowest range possible to prevent instrument damage
考题
单选题The holding power of an anchor increases when the（）.A
amount of chain lying along the bottom increasesB
length of the catenary is reducedC
mooring line tension is increasedD
amount of chain lying along the bottom decreases
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单选题When current and voltage reach maximum values at the same time, the power factor is（）A
minimumB
maximumC
leadingD
lagging
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单选题A power-driven vessel，when towing astern，shall show（）.A
two towing lights in a vertical lineB
a towing light in a vertical line above the sternlightC
two towing lights in addition to the sternlightD
a small white light in lieu of the sternlight
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单选题The easiest way to anchor a vessel in a current is to（）.A
stem the current and make very slow headway when the anchor is droppedB
stem the current and be falling aft very slowly when the anchor is droppedC
stem the current and endeavor to make neither headway nor sternway when the anchor is droppedD
stop all headway through the water and keep the current astern when the anchor is dropped
考题
单选题When the voltage remains constant and the resistance is increased in a series circuit, the flow of current （）A
increases by the square of the original valueB
increasesC
remains the sameD
decreases
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单选题Your portable computer is in sleep mode. When you resume work on the portable computer， you are not prompted for a password. You need to ensure that you are prompted for a password each time the portable computer recovers from sleep mode. What should you do？（）A
Configure the computer to hibernate when not in use.B
In the current power plan settings， configure the computer to require a password when recovering from sleep mode.C
Configure the computer to use the High Performance power plan.D
Configure the screen saver settings to require a password on resumption of work.
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