The moment acting on the rudder of a submarine is investigated by a 1 / 50 scale model. The model is tested in a tunnel where the moment is found to be 2 Nm at a speed of 8 m/s. What are the...

The moment acting on the rudder of a submarine is investigated by a 1 / 50 scale model. The model is tested in a tunnel where the moment is found to be 2 Nm at a speed of 8 m/s. What are the corresponding moment and speed of the prototype assuming both operate in the seawater?

A large valve has an inlet diameter of 5 cm conveying a discharge at the rate of 2.0
/s. A model for this valve is tested in the laboratory, where the same water was used at the same temperature as in the prototype. The inlet diameter for the tested valve is 5 cm. Determine the required discharge in the model.