更多"Variation is not constant; it is di"的相关试题:
[单项选择]When you turn on the fast time constant (differentiator) control of a radar it will（）.
A. enhance weak target echoes and brighten them on the PPI
B. reduce clutter over the entire PPI by shortening the echoes
C. only suppress weak targets to a limited distance from the ship (sea clutter)
D. reduce the beam width to provide a map-like presentation for navigation
[单项选择]The diurnal pressure variation is most noticeable in the（）.
A. polar regions
B. horse latitudes
C. roaring forties
D. doldrums
[单项选择]The diurnal variation of pressure is most noticeable（）.
A. above the polar circles
B. in a low pressure area
C. during periods of low temperatures
D. in the doldrums
[单项选择]Which word indicates color variation in the characteristics of a light?（）
A. Opposing
B. Changing
C. Reversing
D. Alternating
[单项选择]When comparing different fuels for different engines, the ignition quality of diesel fuel oils becomes a less critical consideration as （）
A. the amount of lube oil additives increase
B. piston speeds increase
C. injection pressure decrease
D. engine speeds decrease
[单项选择]Variation is the angular measurement between（）.
A. compass north and magnetic north
B. compass north and true north
C. magnetic meridian and the geographic meridian
D. your vessel's heading and the magnetic meridian
[单项选择]The fact that different languages have different words for the same object is good proof that human language is （）.
A. arbitrary
B. non-arbitrary
C. logical
D. non-productive
[单项选择]Jitter is an unwanted variation of one or more characteristics of a periodic signal in electronics and telecommunications and（）refers to call issues that cause variations in timing or time of arrival.
A. echo
B. jitter
C. packet loss
D. digitized sampling
[单项选择]The variation for most given areas undergoes（）change，the amount of which is also noted on charts.
A. an annual
B. a constant
C. a variable
D. an unstable
[单项选择]Variation is a compass error that you（）.
A. can correct by adjusting the compass card
B. can correct by adjusting the compensating magnets
C. can correct by changing the vessel's heading
D. cannot correct
[单项选择]Variation in a compass is caused by（）.
A. worn gears in the compass housing
B. magnetism from the earth's magnetic field
C. magnetism within the vessel
D. lack of oil in the compass bearings
[单项选择]Magnetic variation changes with a change in（）.
A. the vessel's heading
B. sea conditions
C. seasons
D. the vessel's position
[单项选择]How is variation indicated on a small-scale nautical chart?（）.
A. Magnetic compass table
B. Magnetic meridians
C. Isogonic lines
D. Variation is not indicated on small-scale nautical charts
[单项选择]Constant cooling the various components of diesel engine has a number of functions except for （）.
A. good lubrication
B. low thermal stress
C. good mechanical properties
D. acid corrosion
[单项选择]Constant superheat is maintained at the evaporator outlet of a refrigeration coil by a（）
A. solenoid valve
B. low pressure cutout switch
C. king valve
D. thermal expansion valve
[单项选择]Among the possible causes of unexpected constant inclination of the floating shhip is（）.
A. consumption of on board liquids
B. miscalculation of loads
C. liquid transfer through open valves
D. flooding due to hull damage
[单项选择]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 value
B. increases
C. remains the same
D. decreases
