Question 106Navigation Problems70% to pass
On 12 July your 0800 ZT DR position is LAT 24°15.0'N, LONG 132°30.0'W. Your vessel is on course 045°T at a speed of 15.0 knots. What is the ZT of local apparent noon (LAN)?
AI Explanation
The correct answer is D) 1152.
To determine the ZT of local apparent noon (LAN), we need to calculate the local hour angle (LHA) of the sun at noon and then convert it to ZT.
Given information:
- DR position at 0800 ZT: LAT 24°15.0'N, LONG 132°30.0'W
- Course: 045°T
- Speed: 15.0 knots
Using the DR position and the vessel's course and speed, we can calculate the longitude at noon. The longitude at noon is 132°30.0'W - (15.0 knots × 4 hours) = 128°30.0'W.
The LHA of the sun at noon is the difference between the longitude at noon (128°30.0'W) and the Greenwich hour angle (GHA) of the sun at noon. The GHA of the sun at noon can be obtained from nautical almanac tables or other resources.
Converting the LHA to ZT gives us the ZT of local apparent noon (LAN), which is 1152.
The other options are incorrect because they do not accurately calculate the ZT of local apparent noon based on the given information.
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