A smooth hard rubber tire (modulus of elasticity and Poisson's ratio are: E=5MPa, ν =0.5) with diameter 500mm and width 250mm is running at 25 m/s on a flat wet concrete surface. For the concrete, E= 10 GPA and ν =0.1. Water on the surface has a viscosity of 1 mPa-s. The load on the tire is 5kN. Assume the pressure-viscosity coefficient for water is 0.005 MPa-1.
Using the Dowson and Higginson's equation, what is the minimum film thickness?