Question 422Navigation General
70% to passThe Light List indicates that a light has a nominal range of 8 miles and is 48 feet(14.6 meters) high. If the visibility is 6 miles and your height of eye is 35 feet(10.7 meters), at what approximate distance will you sight the light?
The correct answer is B) 5.9 nm. To determine the distance at which the light will be sighted, we need to use the formula for the geographic range of a light, which is the distance at which the light can be seen above the horizon. The formula is: Distance = 2.08 * (sqrt(height of eye) + sqrt(height of light)). Given information: - Light height: 48 feet (14.6 meters) - Height of eye: 35 feet (10.7 meters) - Visibility: 6 miles Plugging the values into the formula: Distance = 2.08 * (sqrt(10.7) + sqrt(14.6)) Distance = 2.08 * (3.27 + 3.82) Distance = 2.08 * 7.09 Distance = 14.7 nm However, the visibility is limited to 6 miles, so the actual distance at which the light will be sighted is 5.9 nm, which is the correct answer. The other options are incorrect because: A) 12.4 nm is too far, as it exceeds the visibility range. C) 8.0 nm is too far, as it exceeds the visibility range. D) 15.0 nm is too far, as it exceeds the visibility range.
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