Surface tension is due to uneven molecular attraction between immiscible fluid media and solid surface. Its importance is governed by dimensionless parameter Which of the Inertia force called Weber number given by We = Surface tension force™ following statements are correct? (i) Surface tension becomes important when the length scale L is small such as in ink jet printing, coating of thin film, oxygenation of water by falling rain drops. (ii) 111 Super-hydrophobicity can be achieved by micro/nano texturing of surface such as in lotus leave, butterfly and dragonfly wing. During oil spill in ocean, oil floats and spreads out due to gravity. By conservation of mass, the oil film becomes thinner as it spreads. Finally, the surface tension force becomes important causing the formation of tiny oil droplets. (A) (B) (C) (D) (i) and (ii) (i) and (iii) (ii) and (iii) All of the above

Surface tension is due to uneven molecular attraction between immiscible fluid media and solid surface. Its importance is governed by dimensionless parameter Which of the Inertia force called Weber number given by We = Surface tension force™ following statements are correct? (i) Surface tension becomes important when the length scale L is small such as in ink jet printing, coating of thin film, oxygenation of water by falling rain drops. (ii) 111 Super-hydrophobicity can be achieved by micro/nano texturing of surface such as in lotus leave, butterfly and dragonfly wing. During oil spill in ocean, oil floats and spreads out due to gravity. By conservation of mass, the oil film becomes thinner as it spreads. Finally, the surface tension force becomes important causing the formation of tiny oil droplets. (A) (B) (C) (D) (i) and (ii) (i) and (iii) (ii) and (iii) All of the above

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.9P: When a sphere falls freely through a homogeneous fluid, it reaches a terminal velocity at which the...

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