Question 70Navigation General70% to pass
The Light List indicates that a light has a nominal range of 13 miles and is 36 feet high. If the visibility is 17 miles and your height of eye is 25 feet, at what approximate distance will you sight the light?
AI Explanation
The correct answer is B) 12.9 miles.
The reasoning is based on the formula for the geographic range of a light, which is:
Geographic range (in nautical miles) = 2.08 x (square root of the height of the light (in feet) + square root of the height of eye (in feet)).
Given the information provided:
- Light height: 36 feet
- Height of eye: 25 feet
Plugging these values into the formula:
Geographic range = 2.08 x (square root of 36 + square root of 25)
= 2.08 x (6 + 5)
= 2.08 x 11
= 12.9 miles
The other options are incorrect because they do not accurately apply the formula for geographic range of a light. Option A is too low, option C is too high, and option D is the visibility range, not the geographic range.
Related Questions
#68 The light characteristic of flashing is used in the Aids to Navigation System on the Western Rivers for lights on _______________.#69 The Light List shows that a navigational light has a nominal range of 22 miles and a height above water of 48 feet (14.6 meters). Your height of eye is 35 feet (10.7 meters) and the visibility is 20.0 miles. At what approximate range will you first sight the light? #71 You sight a buoy fitted with a double-sphere topmark. If sighted at night, this buoy would show a _______________.#72 The Light List indicates that a light has a nominal range of 14 miles and is 42 feet high (12.8 meters). If the visibility is 6 miles and your height of eye is 20 feet (6.1 meters), at what approximate distance will you sight the light? #73 Coast Pilots and navigational charts are kept corrected and up-to-date by using the _______________.