Question 160Navigation General70% to pass
The Light List shows that a navigational light has a nominal range of 5 miles and a height above water of 21 feet (6.4 meters). Your height of eye is 32 feet (9.8 meters) and the visibility is 1.0 mile. At what approximate range will you first sight the light?
AI Explanation
The correct answer is B) 1.5 miles.
The reasoning is based on the formula for the geographical range of a light, which is determined by the observer's height of eye and the height of the light above the water. The formula is: Geographical range (in nautical miles) = 2.02 * (square root of observer's height of eye in feet) + 2.02 * (square root of the light's height above water in feet).
Given the information provided, the observer's height of eye is 32 feet, and the light's height above water is 21 feet. Plugging these values into the formula, the calculated geographical range is approximately 1.5 miles, which matches the correct answer choice.
The other answer choices are incorrect because A) 1.0 mile is less than the calculated range, C) 5.0 miles is the nominal range of the light, and D) 11.7 miles is significantly greater than the calculated range.
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