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单选题
The points on the earth’s surface where the magnetic dip is 90° are（）.
A
Along the magnetic equator
B
Connected by the isoclinal line
C
The isopors
D
The magnetic poles
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____ is covered with heavy snow.
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Magnetic dip is a measurement of the angle between the ______.A.geographic pole and the magnetic poleB.lubber’s line and true northC.horizontal and the magnetic line of forceD.compass heading and the magnetic heading
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考题
单选题Deviation is caused by（）.A
changes in the earth's magnetic fieldB
nearby magnetic land masses or mineral depositsC
magnetic influence inherent to that particular vesselD
the magnetic lines of force not coinciding with the lines of longitude
考题
单选题Compass deviation is caused by（）.A
magnetism from the earth's magnetic fieldB
misalignment of the compassC
magnetism within the vesselD
a dirty compass housing
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单选题The magnetic compass magnets are acted on by the horizontal component of the Earth’s total magnetic force. This magnetic force is GREATEST at the（）.A
north magnetic poleB
south magnetic poleC
magnetic prime vertical meridianD
magnetic equator
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单选题Which statement about the Flinders bar of the magnetic compass is CORRECT（）.A
It compensates for the error caused by the vertical component of the Earth's magnetic fieldB
It compensates for error caused by the heeling of a vesselC
It compensates for quadrantal deviationD
It is only needed in equatorial waters
考题
单选题If a magnetic compass is not affected by any magnetic field other than the Earth’s，which statement is TRUE? （）A
Compass error and variation are equalB
Compass north will be true northC
Variation will equal deviationD
There will be no compass error
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单选题Geological evidence suggests that the earth’s magnetic polarity has switched back and forth many times over the millennia; such ______in the magnetic field may affect the ability of our planet to ward off cosmic radiation.A
intensificationsB
justificationsC
recordsD
correlationsE
fluctuations
考题
单选题A plane perpendicular to the polar axis will never form what line on the Earth’s surface? （）A
Great circleB
EquatorC
Small circleD
Meridian
考题
单选题During the transition of the Earth’s magnetic field _____.A
the compass will become uselessB
man and animals will be confused as to directionsC
the magnetic strength of the Earth will disappearD
the magnetic strength of the Earth will be stronger
考题
单选题Magnetic dip is a measurement of the angle between the（）.A
geographic pole and the magnetic poleB
lubber's line and true northC
horizontal and the magnetic line of forceD
compass heading and the magnetic heading
考题
单选题Variation in a compass is caused by（）.A
worn gears in the compass housingB
magnetism from the earth's magnetic fieldC
magnetism within the vesselD
lack of oil in the compass bearings
考题
单选题According to the passage, _____.A
we should not worry about the transition of the Earth’s magnetic fieldB
the Earth’s magnetic field will not change for at least 2000 yearsC
the Earth’s magnetic field has decreased its strength rapidlyD
the transition of the Earth’s magnetic field can be controlled by modern science
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单选题Without the sun’s light _____ the earth’s surface, it would be so cold that life could not exist on the earth.A
warmsB
warmedC
warmingD
to warm
考题
单选题What is an advantage of the magnetic compass aboard vessels?（）A
Compass error is negligible at or near the earth's magnetic polesB
It does not have to be checked as oftenC
It is reliable due to it's essential simplicityD
All points on the compass rose are readily visible
考题
单选题What is the basic principle of the magnetic compass（）.A
Magnetic materials of the same polarity repel each other and those of opposite polarity attractB
The Earth's magnetic lines of force are parallel to the surface of the EarthC
Magnetic meridians connect points of equal magnetic variationD
The compass needle（s）will，when properly compensated，lie parallel to the isogonic lines of the Earth
考题
单选题_____ most of the earth's surface is covered by water, fresh water is very rare and precious.A
AsB
OnceC
IfD
Although
考题
单选题The line which connects the points of zero magnetic dip is（）.A
An agonic lineB
The magnetic equatorC
A magnetic meridianD
All of the above
考题
单选题Permanent magnetism is caused by（）.A
operation of electrical equipment and generators on board shipB
the earth's magnetic field affecting the ship's hard iron during constructionC
the horizontal component of the earth's magnetic field acting on the horizontal soft ironD
the vertical component of the earth's magnetic field acting on the vertical soft iron
考题
单选题A ship under construction or major repair will acquire permanent magnetism due to（）while sitting stationary in the earth’s magnetic field.A
hammering and jarringB
vibration and poundingC
varying magnetic fieldsD
stable or permanent magnetism of the ship
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