At 2142, on January 3, you pass Sebastapol...

Question 1 of 2707066636eea28f7522a1c51acd3

At 2142, on January 3, you pass Sebastapol Light (mile 283.3 AHP). At 0137, January 4, you pass Fort Adams Light (mile 311.4 AHP). You have been turning for 9.0 mph. What was the current?

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Question 1 of 27070

At 2142, on January 3, you pass Sebastapol Light (mile 283.3 AHP). At 0137, January 4, you pass Fort Adams Light (mile 311.4 AHP). You have been turning for 9.0 mph. What was the current?

🔍 Key Concepts

• Speed = Distance / Time relationship for computing actual speed made good over the ground • Careful conversion of elapsed time across midnight (from 2142 to 0137 next day) into hours and decimals of an hour • Difference between speed through the water (engine setting/“turning for”) and speed over the ground (affected by current)

💭 Think About

• First, compute the exact elapsed time between the two times, making sure you handle the change of date correctly. Is it more or less than 4 hours? • Use the mileage between the lights to find your actual speed over the ground. Is this faster or slower than the 9.0 mph you are turning for? • Based on that comparison, should the current be with you or against you, and by about how many mph?

✅ Before You Answer

• Verify the distance run by subtracting the two river miles correctly • Convert minutes to decimal hours accurately (minutes ÷ 60) before using the speed formula • When you subtract to find current, pay attention to the sign: if your actual speed over ground is less than 9.0 mph, the current is against you; if greater, it’s with you