Problem 8 (Adhesion vs. Cohesion] A. Water has an angle of contact equal to 118 with a certain type of plastic. The surface tension of water (with itself) is 0.07 N/m. What is the adhesive surface tension between water and this plastic? Give your answer in units of Wm. B. When drops of water are placed on a surface made of this type of plastic, do the drops bead up (like on wax), or spread out (like on glass)? a. Bead up b. Spread out c. Not enough information to decide Fc Sino y KFC Coso Fo Fa A dhesive force between water and plastic will be Fa = Fc sino Fa = (0. 07 ) sin( 118 ) Fa = (0.07 ) (0 - 882947 ) Fa = 0- 06 18 Fa = 0 -062 N B ) When 9790" then drops of water Bead up like wax when then drops of water spread out like glass so in this Case 0 7 90 " then they will Bead up