更多"Fog forms when the air（）."的相关试题:
[单项选择]Fog forms when the air（）.
A. is 50% water saturated
B. is 90% water saturated
C. temperature is greater than the dew point temperature
D. temperature is equal to，or below the dew point temperature
[单项选择]When the air charge contacts with the cylinders and pistons and mixes with the residual gases, it will（）
A. increase in temperature
B. lose its energy partly
C. expand and do work
D. begin to be compressed
[单项选择]When starting air is admitted, a diesel engine turns over very slowly without firingThe cause may be （）
A. an obstruction in an cylinder
B. water accumulation in some engine cylinders
C. low starting air pressure
D. low scavenge air pressure
[单项选择]
When starting air-conditioner in the winter, we should open（）in sequence.
Ⅰ.alve of warming
Ⅱ.alve of humidifier
Ⅲ.an
A. Ⅲ-Ⅱ-Ⅰ
B. Ⅲ-Ⅰ-Ⅱ
C. Ⅰ-Ⅲ-Ⅱ
D. Ⅱ-Ⅲ-Ⅰ
[单项选择]What occurs when rising air cools the dew point?（）
A. advection fog forms
B. humidity decrease
C. wind increase
D. Cloud form
[单项选择]When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）
A. intake stroke
B. compression stroke
C. power stroke
D. exhaust stroke
[单项选择]In reference to air conditioning, when air attains the maximum amount of moisture it can hold at a specific temperature, it is said to be （）.
A. superheated
B. saturated
C. condensed
D. convected
[单项选择]What is TRUE when operating in fog and other vessels are detected by radar?（）.
A. You should make an ample change to port for a vessel crossing on the starboard bow
B. You should maneuver in ample time if a close-quarters situation is developing
C. You should determine the course and speed of all radar contacts at six minute intervals
D. Long-range scanning will provide early warning of ALL other vessels within the radar's range
[单项选择]The fog produced by warm moist air passing over a cold surface is called（）.
A. conduction fog
B. radiation fog
C. frontal fog
D. advection fog
[单项选择]Advection fog may be formed by cold air passing over a（）.
A. colder sea surface
B. warmer sea surface
C. dry coastal plains
D. high mountain or plateau
[单项选择]When your vessel enters thick fog，she should sound（）every two minutes in accordance with these Rules.
A. one short blast
B. one prolonged blast
C. two short blasts
D. three short blasts
[单项选择]When navigating in thick fog with the radar on，you should（）.
A. station the look-out in the wheelhouse to keep a continuous watch on the radar
B. secure the sounding of fog signals until a vessel closes within five miles
C. station a look-out as low down and far forward as possible
D. keep the radar on the shortest available range for early detection of approaching vessels
[单项选择]When air becomes trapped in the hydraulic fluid of a steering system, the （）.
A. rudder will respond sluggishly
B. hydraulic rams will over-speed
C. sight glass will show bubbles
D. ram relief valves will lift
[单项选择]When vessel enters thick fog, she should sound（）every two minutes in accordance with the rules.
A. one short blast
B. one prolonged blast
C. two short blasts
[单项选择]Fog is likely to occur when there is little difference between the dew point and the（）.
A. relative humidity
B. air temperature
C. barometric pressure
D. absolute humidity
[单项选择]When using a high-velocity fog stream in a passageway，the possibility of a blow back must be guarded against. Blow back is most likely to occur when（）.
A. pressure builds up in the nozzle which causes a surge of water
B. the only opening in a passageway is the one from which the nozzle is being advanced
C. pressure in the fire hose drops below 100 psi
D. a bulkhead collapses due to heat and pressure
[单项选择]When operating the air supply system in a covered lifeboat the（）.
A. fuel supply valve should be closed
B. hatches，doors，and oar ports should be closed
C. air cylinder shut-off valve should be closed
D. engine should be shut off
[单项选择]When the starting air valve closes on one cylinder, another starting air valve has （） opened on another cylinder whose piston has just commenced its downward stroke.
A. just
B. nearly
C. merely
D. already
