What wind velocity is required to topple an empty tractor trailer, as shown here? The trailer is 48 ft long, 8 ft wide, 12 ft tall, and the trailer floor is 4 ft above the road surface, giving the trailer a square cross section. It weighs 13,500 lb. Assume the air p= 0.0023 slug/ft³ and kinematic viscosity v = 1.5 x10+ ft²/s.

Oil Coating: A long, continuous belt is pulled upwards through a chemical oil bath at velocity V0. The belt has rectangular cross-section and has length (L), width into the paper (W). The belt picks up a film of oil of thickness h, density ρ, and dynamic viscosity μ. Gravity g tends to make the oil drain down, but the movement of the belt keeps the fluid from running off completely. Assume fully developed, steady, laminar, incompressible and two-dimensional flow of oil to answer the following questions. Assume that no pressure gradient is needed in the vertical direction to drive the film flow. Also assume that the shear stress at the air-oil interface is zero (free shear condition). Assume no-slip condition for the fluid in contact with the moving belt. Justify any other assumptions you may make. Show all steps. (a) Derive an expression for the two-dimensional velocity field inside the oil film in terms of the known parameters. Clearly indicate your co-ordinates and origin. You must…

6. A hydraulic lift (see below) of the type commonly used for greasing automobiles consists of a 280.00 mm diameter ram which slides in a 280.18 mm-diameter cylinder, the annular space being filled with oil film of thickness t = 0.09 mm, having a viscosity 0.3612 kg/(m s). If the rate of travel of the ram is v= 0.22 m/s, find the frictional resistance when 2 m of the ram is engaged in the cylinder. Take the weight of ram as 500 N. Ram Oil film -Fixed cylinder