Q3. A piston having a diameter of 14 cm and a length of 25 cm slides downward with a constant velocity V through a vertical hollow cylinder. The downward motion is resisted by an oil film between the piston and the hollow cylinder wall. The film thickness is 0.005 cm and the weight of the piston is 2.5 N. Assume the velocity distribution in the gap is linear. (a) (i) Determine V if the oil viscosity is 0.38 N-s/m². (ii) Based on your working from Q3(a)(i), explain one of the ways to increase the piston's velocity. (iii) Indicate in a simple sketch the direction of shear stress acting on the hollow cylinder wall.

Q3. A piston having a diameter of 14 cm and a length of 25 cm slides downward with a constant velocity V through a vertical hollow cylinder. The downward motion is resisted by an oil film between the piston and the hollow cylinder wall. The film thickness is 0.005 cm and the weight of the piston is 2.5 N. Assume the velocity distribution in the gap is linear. (a) (i) Determine V if the oil viscosity is 0.38 N-s/m². (ii) Based on your working from Q3(a)(i), explain one of the ways to increase the piston's velocity. (iii) Indicate in a simple sketch the direction of shear stress acting on the hollow cylinder wall.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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