航海英语潮汐与涌浪章节练习(2017.12.26)

单项选择题
Which current would you encounter on a direct passage from London，England，to Capetown，South Africa（）.
A.Falkland Current
B.Brazil Current
C.Norway Current
D.Benguela Current
单项选择题
The current rates（）excess of 2 kn may occur with prolonged strong winds.
A.by
B.with
C.on
D.in
单项选择题
The two most effective generating forces of surface ocean currents are（）.
A.temperature and salinity differences in the water
B.wind and density differences in the water
C.water depth and underwater topography
D.rotation of the Earth and continental interference
单项选择题
A stream of water immediately surrounding a moving vessel’s hull，flowing in the same direction as the vessel is known as（）.
A.directional current
B.forward current
C.propeller current
D.wake current
单项选择题
Scouring is the result of（）.
A.interruption of the normal current flow by the footing
B.elevating in mud-slide zones
C.penetrating rapidly through a hard crust into weaker soils
D.extracting legs from soils with high cohesion
单项选择题
A structure，usually made of stone，or cement pilings，which extends from the bank at approximately right angles to the current is called a（）.
A.dike
B.revetment
C.cutoff
D.crib
单项选择题
Neap tides occur when the（）.
A.Moon is in its first quarter and third quarter phases
B.Sun and Moon are on opposite sides of the Earth
C.Moon's declination is maximum and opposite to that of the Sun
D.Sun and Moon are in conjunction
单项选择题
Spring tides are tides that（）.
A.have lows lower than normal and highs higher than normal
B.have lows higher than normal and highs lower than normal
C.are unpredictable
D.occur in the spring of the year
单项选择题
The set of the equatorial countercurrent is generally to the（）.
A.north
B.east
C.southwest
D.northwest
单项选择题
Stand of the tide is that time when（）.
A.the vertical rise or fall of the tide has stopped
B.slack water occurs
C.tidal current is at a maximum
D.the actual depth of the water equals the charted depth