The dimensionless ratio U??/ ?? Lg, called Froude number, is a measure of similarity between an ocean-going ship and a scale model of the ship to be tested in a laboratory water channel. A 500 ft long cargo ship is designed to run at 20 knots, and a 5 ft. geometrically similar model is towed in a water channel to study wave resistance. What should be the towing speed in m s??1?GIVENA ship model and its prototypeFroude number = U??/ ??Lg is a measure of similarityShip length (Ls) = 500 ftShip speed (U??s) = 20 knotsModel length (Lm) = 5ft

U-m"? Us- 20 knots Lm -5ft 4= 500 ft- Ship Prototype Model