Q. An oil of vicosity 7 poise is used for lubrication between shaft and sleeve. The diameter of shaft is 0.6 m and it rotates is 360 rpm. Calculate the power lost in oil for a sleeve length of 160mm. The thickness of oil film is 1.0mm.

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Q. Find the capillarity rise or fall if a capillary tube of diameter .03m is immersed in hypothetical fluid with specific gravity 6.5, surface tension 0.25 N/m and angle of contact 147°.

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Q. Will capillary rise occur and if it occurs what will be capillary rise if glass capillarity tube is immersed in water and experiment is carried out by astronauts in space.

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Q. The surface tension of fluid in contact with air at 25℃ is 0.51N/m. The pressure inside a droplet is to be 0.05 N/cm² greater than outside pressure. Determine the diameter of the droplet of water.

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Q. If a fluid of certain surface tension and diameter is used to create a soap bubble and a liquid jet. Which of the two, bubble or liquid jet, will have greater pressure difference on the inside and outside.

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Q. Capillarity fall is reduced if we take the appartus (capillary tube immersed in fluid having acute angle of contact) considerable distance inside the earth( i.e below the earth crust).

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Q. For liquid fluids will capillarity rise (or fall) increase or decrease with rise in temperature.

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Q. Cavitation is more pronounced in rough pipes than smooth surfaced pipes.

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Q. The space between two plates (20cm*20cm*1cm), 1 cm apart, is filled with a liquid of viscosity 1 Poise. The upper plate is dragged to the right with a force of 5N keeping the lower plate stationary.
What will be the velocity in m/s of flow at a point 0.5 cm below the lower surface of the upper plate if linear velocity profile is assumed for the flow?

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Q. The graph shows relation between shear stress Z and velocity gradient du/dy of a fluid is given by Z = A * (du/dy)ⁿ where A and n are constants. The graphs are drawn for three values of n. Which one will be the correct relationship between n₁, n₂ and n₃?

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Q. A soap film is trapped between a frame and a wire of length 10 cm as shown. If the surface tension is given as 0.0049 N/m, what will be the value of m (in mg) such that the wire remains in equilibrium?

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