Flashcards in Exam 2 Deck (57):
The moon will rise approximately how many minutes later each night if you are at the same location?
What is the difference between a course line and a Trak line?
A course line is the intended direction of travel, always drawn as the true course on a chart.
A track line is the actual path of the vessel determined by plotting, which would be your course made good.
Only a single high and low water each title day is referred to as
Water takes time to build momentum to full speed and also takes time to reduce from full speed to be 0 kn
What factor has the greatest effect on title currents?
How do you mark an estimated position?
With a square
Can currents be caused by wind, rain, or the slope of land?
What is the bow and beam bearing rule?
45 to 90° relative taken on a fixed object to obtain a running fix. The length of the run between such bearings is equal to the distance of the craft from the object of the time the object is brought on the beam.
What is the Coriolis force?
Northern hemisphere to the right
Describe the stand of the tide
And interval at high or low water when there is no sensible change in the height of the tide
What is mixed tide?
Large inequality in the high and low water Heights
How much time is in a lunar day?
Approximately 24 hours and 50 minutes
What do you do to correct leeway?
Turn into the set
Tidal current is the____Movement of water and is caused by tide. Current is said to___
Horizontal; flood or Ebb
Speed along the track made good is the
Speed made good
If you were trying to take advantage of the higher high tide of a spring tide be sure to understand that
The low tide will be a lower tide
It’s always best to dock during slack tide.
The direction in which the current flows
What direction does wind come from?
From the direction it is named
What are characteristics of neap Tide?
These are tides of decreased range or speed, occur semi monthly, result of moon being in quadrature.
How do you mark a dead reckoning?
With the half circle
What is a rotary current?
The direction of flow is not restricted by land barriers and rotates through all points of the compass. They’re tidal currents that occur offshore away from land or harbor constrictions; the northern hemisphere is clockwise and the southern hemisphere is counterclockwise.
A horizontal movement of water
How do you mark a fix?
With a circle
The difference in height between consecutive high and low waters
What is the term leeway used to account for?
The deviation from the course by wind
How do you mark an electronic fix?
With a triangle
Where does the gulf stream begin?
The Straits of Florida between the Florida Keys and Cuba
What is Tide?
The vertical rise and fall of water
The periodic rise and fall of the water resulting from gravitational interactions between the sun moon and earth
What is the 26.5 to 45° rule?
The distance run between bearings equals the distance off when a beam.
Where do diurnal tides occur?
The northern shore of the Gulf of Mexico, Java sea, gulf of Tonkin, and a few other locations
2 high and 2 low water each day is referred to as
What are some other determining factors and tidal currents?
Configuration of basin, friction, landmasses, inertia of water masses, Coriolis acceleration
How long is a lunar month?
Area of the sea surface over which seas are generated by a wind having a constant direction and speed is known as
A ships actual position will be___from a dead reckoning position due to___
What is a hydraulic current?
A current in a channel caused by a difference in the surface level at the two ends
Describe slack water
The period of time where water changes direction of flow i.e. has no current, and speed of the current is near zero.
What is leeway?
The angular difference between a vessels course in the track due to the effect of the wind moving a vessel bodily to leeward.
Wind is described as the direction it’s coming from.
What is the 7/10 rule?
States that the appropriate distance to an object brought on the beam equals 7/10 of the distance traveled by a craft while the relative bearing changes from 22.5° to 45°.
Ocean currents are fairly stable regular and well-defined and extend over long distances.
Toward the Lee or in that general direction toward which the wind is blowing.
(the opposite of windward)
What is Slack?
The period of high or low water when there is no change in the height of water
Set is described as
To or towards
What is flood?
The movement of water towards shore or upstream.
The rise and fall of the tide is not uniform.
The Gulf Stream is characterized as
A Swift high saline current of Bluewater who’s upper Stratham is composed of warm water
The single resultant directions from a point of departure to a point of arrival at any given time is the
Course made good
What direction does current flow?
Towards the direction it is named
Tide is___Movementof water and is said to___.
Vertical; rise or fall
Describe the double the angle on the bow rule
The angular distance of the object on the bow is doubled, the distance run between bearings equals the object distance at the second bearing.
How is set and drift measured?
From a dead reckoning to a fix
The speed of the current/knots per hour
What is EBB?
The movement of water away from shore or downstream.