A block of weight $W$ slides down an inclined plane while lubricated by a thin film of oil, as in Fig. P1.45. The film contact area is $A$ and its thickness is $h .$ Assuming a linear velocity distribution in the film, derive an expression for the "terminal" (zero-acceleration) velocity $V$ of the block. Find the terminal velocity of the block if the block mass is $6 \mathrm{kg}, A=35 \mathrm{cm}^{2}, \theta=15^{\circ},$ and the film is $1-\mathrm{mm}$ -thick SAE 30 oil at $20^{\circ} \mathrm{C}$