A particular submarine is capable of cruising at 20 km/h at the surface of the ocean and far below the surface of the ocean. Tests of both of these conditions are to be performed using a 1:40 scale...

A particular submarine is capable of cruising at 20 km/h at the surface of the ocean and far below the surface of the ocean. Tests of both of these conditions are to be performed using a 1:40 scale model of the submarine. Determine the required model speed and the ratio of prototype drag to model drag for the following model conditions: (a) a model of cruising on the surface and (b) a model of cruising far below the surface. Assume that the prototype ocean water properties can be duplicated in the model tests.