Q. Determine the minimum size of glass tube that can be used to measure water level if the capillary rise in the tube is restricted to 5mm. Consider surface tension of water in contact with air as 0.073 N/m.

View solution

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.

View solution

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°.

View solution

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.

View solution

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.

View solution

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.

View solution

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).

View solution

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

View solution

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

View solution

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?

View solution

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?

View solution

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?

View solution