This is an interactive test. Read each question and select the proper answer by clicking on the appropriate answer. If a "Y" appears, your choice is correct. If a "N" appears, more study may be in order.
12: Lines on a chart which connect points of equal magnetic variation are called __________.
N a. magnetic latitudes N b. magnetic declinations N c. dip Y d. isogonic lines 103: In Loran-C the high accuracy of atomic time and frequency controls allows each station to operate __________.
N a. at higher frequencies Y b. on schedule, independently N c. at 1,975 kHz N d. in a multiplex phase 110: A millibar is a unit of __________.
N a. humidity N b. precipitation Y c. pressure N d. temperature 111: Green lights may appear on __________.
Y a. horizontally banded buoys N b. vertically striped buoys N c. yellow buoys N d. spherical buoys 164: The part of a sextant mounted directly over the pivot of the index arm is the __________.
Y a. index mirror N b. horizon glass N c. micrometer drum N d. telescope 175: On 5 July 1981, at 1200 zone time, you cross the 180th meridian steaming westward. What is your local time?
N a. It is 1200, 4 July. N b. It is 1200, 5 July. Y c. It is 1200, 6 July. N d. It is 2400, 6 July. 256: The belt of light and variable winds between the westerly wind belt and the northeast trade winds is called the __________.
Y a. subtropical high pressure belt N b. intertropical convergence zone N c. doldrum belt N d. polar frontal zone 330: You are taking bearings on two known objects ashore. The BEST fix is obtained when the angle between the lines of position is __________.
Y a. 90° N b. 30° N c. 45° N d. 60° 365: The Sun at a maximum declination north would be approximately at __________.
Y a. aphelion N b. perihelion N c. autumnal equinox N d. first point of Aries 422: If you are sailing from the East Coast of the United States to the Caribbean Sea, which publication would contain information on weather, currents, and storms?
N a. Sailing Charts of the Caribbean Sea Y b. Pilot Charts of the North Atlantic N c. Light Lists, Atlantic and Gulf Coast N d. Tidal Current Tables 425: 90° - Ho = __________.
N a. sextant altitude N b. co-latitude N c. LHA Y d. zenith distance 543: A radar display which is oriented, so that north is always at the top of the screen, is called a(n) __________.
N a. relative display N b. composite display Y c. stabilized display N d. unstabilized display 605: Which is NOT a side of the celestial navigational triangle?
N a. Co-latitude N b. Zenith distance Y c. Altitude N d. Co-declination 613: Your radar indicates a target; however, there is no visible object at the point indicated. A large mountain, approximately 50 miles away on the same bearing as the target, is breaking the horizon. You should suspect the radar target is caused by __________.
N a. a submerged submarine Y b. ducting N c. sub-refraction N d. ionospheric skip waves 648: Weather systems in the middle latitudes generally travel from __________.
N a. north to south Y b. west to east N c. east to west N d. None of the above 812: You are informed of defects or changes in aids to navigation by __________.
N a. Local Notice to Mariners N b. Weekly Notice to Mariners N c. marine broadcasts Y d. All of the above 918: At 1200 ZT, on 31 August, your position is LAT 43°14'S, LONG 175°44'E. You are preparing a weather report form, WS Form B-80. How should you encode the first three groups after the call sign if you estimate the wind? (D041NG )
N a. 01003, 94314, 51757 Y b. 31003, 99432, 31757 N c. 31123, 99432, 31754 N d. 31243, 94314, 31757 945: What is NOT a side of the navigational triangle used in sight reduction?
Y a. Altitude N b. Zenith distance N c. Colatitude N d. Polar distance 969: The population of northern right whales, an endangered species, numbers approximately __________.
Y a. 300 N b. 5000 N c. 100,000 N d. 1,000,000 1008: The Light List indicates that a light has a nominal range of 18 miles and is 38 feet high. If the visibility is 6 miles and your height of eye is 15 feet, at which distance will you sight the light?
N a. 18.0 nm N b. 14.8 nm Y c. 11.7 nm N d. 6.0 nm 1008: The Light List indicates that a light has a nominal range of 18 miles and is 38 feet high. If the visibility is 6 miles and your height of eye is 15 feet, at which distance will you sight the light?
N a. 18.0 nm N b. 14.8 nm Y c. 11.7 nm N d. 6.0 nm 1016: A source of an air mass labeled mTw is __________.
N a. the equator Y b. the Gulf of Mexico N c. Alaska N d. Canada 1025: A first magnitude star is __________.
Y a. 2.5 times as bright as a second magnitude star N b. 3 times as bright as a second magnitude star N c. 5 times as bright as a second magnitude star N d. 10 times as bright as a second magnitude star 1043: You are about to go to sea and adjust the magnetic compass. To expedite the adjustment at sea, in what order should the following dockside adjustments be made?
N a. Flinders bar first, then the heeling magnet and spheres N b. Heeling magnet first, then the Flinders bar and spheres Y c. Flinders bar first, then the spheres and heeling magnet N d. Spheres first, then the Flinders bar and heeling magnet 1044: The dry-bulb temperature is 78°F and the wet-bulb temperature is 62°F. What is the relative humidity?
N a. 16% N b. 24% Y c. 39% N d. 79% 1045: The Light List shows that a navigational light has a nominal range of 15 miles and a height above water of 40 feet (12.2 meters). Your height of eye is 25 feet (7.6 meters) and the visibility is 5 miles. At about what range will you FIRST sight the light?
N a. 6.2 miles Y b. 9.5 miles N c. 12.9 miles N d. 14.2 miles 1092: The wind velocity is higher in the dangerous semicircle of a tropical cyclone because of the __________.
N a. extension of the low pressure ridge Y b. wind circulation and forward motion of the storm N c. recurvature effect N d. direction of circulation and pressure gradient 1098: A chart position enclosed by a square is a(n) __________.
N a. fix Y b. estimated position N c. dead reckoning position N d. running fix 1183: The principal purpose of magnetic compass adjustment is to __________.
N a. reduce the variation as much as possible Y b. reduce the deviation as much as possible N c. reduce the magnetic dip as much as possible N d. allow the compass bowl to swing freely on its gimbals 1189: Concerning a celestial observation, the azimuth angle is measured from the principal vertical circle to the ____________ .
N a. Greenwich celestial meridian N b. hour circle of the body N c. local celestial meridian Y d. vertical circle of the body 1189: Concerning a celestial observation, the azimuth angle is measured from the principal vertical circle to the ____________ .
N a. Greenwich celestial meridian N b. hour circle of the body N c. local celestial meridian Y d. vertical circle of the body 1241: Which picture shows a fixed and flashing light? (D034NG )
Y a. A N b. B N c. C N d. D 1259: General information on enroute weather and climate is found in __________.
Y a. the Sailing Directions and the Coast Pilot N b. a weather fax N c. the Local Notice to Mariners N d. the Light List 1260: On 26 February 1983, at 1750 EST (ZD +5) what will be the predicted height of tide at New Haven (city dock), CT?
N a. -.3 foot (-0.1 meter) Y b. -.6 foot (-0.2 meter) N c. 1.3 feet (0.4 meter) N d. 1.6 feet (0.5 meter) 1301: The four standard light colors used for lighted aids to navigation are red, green, white, and __________.
N a. purple N b. orange N c. blue Y d. yellow 1431: A lighthouse is 120 feet (36.6 meters) high and the light has a nominal range of 18 miles. Your height of eye is 42 feet (12.8). If the visibility is 11 miles, approximately how far off the light will you be when the light becomes visible?
N a. 12.5 miles N b. 16.0 miles Y c. 19.0 miles N d. 23.5 miles 1505: At 0000 you fix your position and change course to 090°T. At 0030 you again fix your position and it is 0.5 mile east of your DR. Which statement is TRUE?
Y a. The current is easterly. N b. The drift is 0.5 knot. N c. You should alter course to the right to regain the track line. N d. The current is perpendicular to your track line. 1520: The diurnal inequality of the tides is caused by __________.
Y a. the declination of the Moon N b. changing weather conditions N c. the Moon being at apogee N d. the Moon being at perigee 1636: A type of precipitation that occurs only in thunderstorms with strong convection currents that convey raindrops above and below the freezing level is known as __________.
N a. sleet Y b. hail N c. freezing rain N d. rime 1727: What enables you to estimate the bearing of a storm's center?
Y a. Buys Ballot's Law N b. An educated guess N c. Pascal's Law N d. The left-hand rule 1811: To find a magnetic compass course from a true course you must apply __________.
N a. deviation Y b. deviation and variation N c. variation N d. magnetic anomalies (local disturbances) 1842: What is the major problem with taking high altitude observations?
N a. Possible errors due to unusual refraction may exist. N b. The tables are not as accurate due to inherent errors in the spherical triangle at high altitudes. N c. Rapidly changing altitudes make it difficult to get an accurate altitude. Y d. It is difficult to establish the point where the sextant is vertical to the horizon. 1874: Lighted white and orange buoys must show which color light?
N a. Orange N b. Red N c. Alternating yellow and white Y d. White 1900: A parallax correction is NOT applied to observations of the __________.
Y a. stars N b. Moon N c. Sun N d. Planets 2085: Information about major breakdowns, repairs, or other emergency operations with regard to weirs and (or) wicket dams, on the western rivers, may be obtained from the __________.
Y a. Broadcast Notice to Mariners N b. Light List Vol. V N c. U.S. Coast Pilot N d. Sailing Directions 2116: Vessels regularly navigating rivers above Cairo, Illinois, shall at all times have on board a copy of the __________.
N a. Nautical Almanac for the year Y b. U.S. Army Corps of Engineers Regulations (Blue Book) N c. Sailing Directions N d. All of the above 2132: What is the definition of height of tide?
N a. The vertical difference between the heights of low and high water N b. The vertical difference between a datum plane and the ocean bottom Y c. The vertical distance from the tidal datum to the level of the water at any time N d. The vertical distance from the surface of the water to the ocean floor 2141: What lights would you see on the Illinois water way when any wickets of the dam or bear traps are open, or partially open, which may cause a set in the current conditions in the upper lock approach?
N a. Red over green N b. Green over red Y c. Red over amber (yellow) N d. Green over amber (yellow) 2279: Antares is found in what constellation?
Y a. Scorpio N b. Corvus N c. Libra N d. Corona Borealis 2358: Altair is found in what constellation?
N a. Hercules N b. Cygnus Y c. Aquila N d. Capricorn 2479: The equation of time measures the __________.
N a. difference between local apparent time and Greenwich apparent time N b. longitude in time units N c. difference between sidereal time and local time at the Greenwich meridian Y d. time between the passage of the mean sun and the apparent sun over a meridian 2630: In the celestial equator system of coordinates what is NOT equivalent to the longitude of the Earth system of coordinates?
N a. SHA N b. t N c. LHA Y d. Zn 2719: Under the U.S. Aids to Navigation System on the Western Rivers, passing daymarks on the right descending bank are __________.
N a. red diamond-shaped panels with red reflector borders N b. red triangular-shaped panels with red reflector borders Y c. green square-shaped panels with green reflector borders N d. green triangular-shaped panels with green reflector borders 2766: In low latitudes, the high(s) of the diurnal variation of pressure occur(s) at __________.
N a. noon N b. noon and midnight Y c. 1000 and 2200 N d. 1600 2801: Mean high water is used __________.
N a. as the reference for soundings on the Gulf coast of the U.S. Y b. to indicate the shoreline where there is a large tidal fluctuation N c. as the reference plane for bottom contour lines N d. as the sounding datum for rivers, lakes, etc. regulated by locks 2819: The time interval between successive wave crests is called __________.
Y a. wave period N b. wavelength N c. frequency N d. significant wave height 2956: On 23 August 1981 you observe a back sight of the upper limb of the Sun. The sextant altitude (hs) is 116°42.8'. The height of eye is 56 feet and the index error is 2.0' off the arc. What is the observed altitude (Ho)?
N a. 63°42.0' N b. 63°38.0' N c. 63°19.4' Y d. 63°06.2' 2973: You should plot a dead reckoning position after every __________.
N a. course change N b. speed change N c. fix or running fix Y d. All of the above 3012: The draw span of a floating drawbridge may be marked with __________.
Y a. a yellow light showing Morse Code (B) N b. a yellow and white diamond N c. flashing blue lights N d. three red lights on each side of the draw 3029: On 13 November 1981 you observe a back sight of the upper limb of the Moon. The sextant altitude (hs) is 110°31.2'. The height of eye is 46 feet and the index error is 2.0' on the arc. The horizontal parallax is 61.3'. What is the observed altitude (Ho)?
N a. 70°11.8' Y b. 69°41.8' N c. 69°25.6' N d. 69°18.4'