You are steering 143°T, and a light is...

Question 1 of 2707066636ee928f7522a1c51a1cf

You are steering 143°T, and a light is picked up dead ahead at a distance of 18.2 miles at 2006. You change course to pass the light 5.5 miles off abeam to port. If you are making 14.5 knots, what is your ETA at a position 5.5 miles off the light?

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Question 1 of 27070

🔍 Key Concepts

• Relative motion in a right triangle when altering course to pass a fixed object abeam at a given distance • Using speed–time–distance: $\text{Time} = \frac{\text{Distance}}{\text{Speed}}$ with speed in knots and distance in nautical miles • Converting decimal hours to minutes and adding them correctly to a given time of day

💭 Think About

• Sketch the situation as a right triangle with your original track toward the light and your new track that will pass 5.5 miles off abeam to port. Which side of the triangle is the 18.2 miles and which is the 5.5 miles? • Once you know where the closest point of approach (CPA) occurs, what distance along your new course do you need to steam before you are abeam of the light at 5.5 miles? • After finding that steaming distance on the new course, how do you convert that distance and your speed in knots into elapsed time, and then into clock time after 2006?

✅ Before You Answer

• Be sure you are using nautical miles with knots so the speed–time–distance formula works directly • Confirm that you are using the correct leg of the triangle for the time calculation — it should be the distance actually steamed after the course change, not just the 18.2 miles or the 5.5 miles alone • Double-check your time conversion from decimal hours to minutes before matching with the multiple-choice times