Question 5Navigation General

70% to pass

The Light List shows that a navigational light has a nominal range of 10 miles and a height above water of 38 feet (11.6 meters). Your height of eye is 52 feet (15.8 meters) and the visibility is 11.0 miles. At which approximate range will you first sight the light?

A 10.5 miles
B 13.9 miles
C 15.6 miles
D 18.0 miles
AI Explanation

The correct answer is A) 10.5 miles. The range at which you will first sight the light is determined by the formula for visual range, which takes into account the height of the light above the water and the height of the observer's eye above the water. Using this formula, with the given information, the approximate range at which you will first sight the light is 10.5 miles. The other options are incorrect because they do not accurately reflect the calculated visual range based on the provided information. Option B) 13.9 miles, C) 15.6 miles, and D) 18.0 miles are all outside the correct range determined by the formula.

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Official Resources
USCG Navigation Rules (COLREGS) 33 CFR Navigation Rules USCG National Maritime Center
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