The drag of a small submarine hull is to be investigated when moving deep below the water surface using a 1 / 10 scale model. At what speed should the model be tested if the submarine is to run at 10...

The drag of a small submarine hull is to be investigated when moving deep below the water surface using a 1 / 10 scale model. At what speed should the model be tested if the submarine is to run at 10 km/h? What drag force on the prototype corresponds to a drag force of 3 kN in the model?