A sphere model of 15 cm diameter is tested in water flowing at 3 m/s. The drag force is measured as 5 N. Prototype of 2 m in diameter is tested in the air with a dynamic similar conditions. Find the drag force experienced by the prototype using the following data:-

Density of air is 1.2 kg/m3; Viscosity of water is 0.001 Ns/m2, Viscosity of air is 1.7 ×  10-5 Ns/m2