🔍 Key Concepts

• Geographic range vs. luminous range of a light and which one limits visibility first in this problem • How to compute time = distance ÷ speed using nautical miles and knots • How to relate present meteorological visibility (6.5 nm) to the charted nominal range of a light (20M)

💭 Think About

• Ask yourself: if the light is nominally visible at 20M, but the current visibility is only 6.5 nm, what is the maximum distance you can see it under these conditions? • Think about your current position on the 240° pgc course line: are you moving toward or away from Point Judith Light when you will lose sight of it? • Once you know the distance from your current position to where you will lose sight of the light, how do you convert that distance at 14.5 knots into minutes of time to add or subtract from your current time?

✅ Before You Answer

• Confirm which is smaller: meteorological visibility (6.5 nm) or the light’s nominal range (20M), and use the limiting one for when you lose sight. • Be sure your speed units (knots) match your distance units (nautical miles) before using the time formula. • Double-check whether your time result should be earlier or later than the time you are currently abeam/on the course line, based on the direction of travel relative to the light.