At 0726 you depart Lake Montauk with light 1...

Question 1 of 29218fork_a033713cb5354783988

At 0726 you depart Lake Montauk with light 1 close aboard and set course 065° per standard magnetic compass at 6.7 knots. At 0912 your GPS position is LAT 41°10.5'N, LONG 71°46.6'W. What is the current?

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Question 1 of 29218

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🔍 Key Concepts

• Set and drift of current found by comparing DR position to a fix • Using course per standard magnetic compass and speed to plot a DR track • Converting the line from DR position to fix into a true direction (set) and a speed (drift)

💭 Think About

• First, compute how much time passed between 0726 and 0912, then use the ordered speed to find how far you should have gone with no current. Which tool/formula lets you do that? • Once you have the DR distance and direction from Lake Montauk Light 1, how do you find the DR position on the chart, and then compare it to the GPS fix? What does the line from DR to GPS represent? • After drawing the vector from DR to GPS, how do you measure its true bearing and its length, and then convert that length into knots over the elapsed time?

✅ Before You Answer

• Be sure you’re using elapsed time in hours when applying $\text{Speed} = \frac{\text{Distance}}{\text{Time}}$ . • Confirm that the set is expressed as the direction toward which the current is flowing, in true degrees (°T). • Verify that the drift (speed of current) is computed as $\text{Drift} = \frac{\text{Distance between DR and fix}}{\text{Elapsed time}}$ and matches one of the answer choices.