🔍 Key Concepts

• How to convert revolutions per minute (RPM) and propeller pitch (feet per revolution) into speed in knots • Relationship between speed (knots), feet per minute, and nautical miles per hour • Meaning of 0% slip when calculating theoretical speed of advance

💭 Think About

• First, calculate how many feet the vessel would move ahead in one minute with 88 RPM and 19 feet of pitch if there is no slip. What is the formula? • Convert your result in feet per minute into nautical miles per hour. What distance in feet equals one nautical mile, and how many minutes are in one hour? • After converting to knots, compare your calculated value with the multiple-choice options and see which is closest.

✅ Before You Answer

• Be sure you multiply RPM × pitch to get feet per minute of advance when slip is 0% • Use 6,076 feet per nautical mile (approximate standard) and 60 minutes per hour for your conversions • Double-check unit consistency at each step so you end with nautical miles per hour (knots), not feet per second or miles per hour