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Mechanical properties of fluid

1 In a laminar flow the velocity of the liquid in contact with the walls of the tub is
(a) Zero
(b) Maximum
(c) In between zero and maximum
(d) Equal to critical velocity
2 In a turbulent flow, the velocity of the liquid molecules in contact with the walls of the tube is
(a) Zero
(b) Maximum
c) Equal to critical velocity
(d) May have any value
3

4 An application of Bernoulli's equation for fluid flow is found in
(a) Dynamic lift of an aeroplane
(b) Viscosity meter
(c) Capillary rise
(d) Hydraulic press
5 As the temperature of water increases, its viscosity
(a) Remains unchanged
(b) Decreases
(c) Increases
(d) Increases or decreases depending on the external pressure
6 Write the dimensional formula of coefficient of viscosity.
7 What is critical velocity?
8 What is critical Reynolds number?
9 For a soap bubble, where is the pressure greater?
10 Using Stoke's law, derive an expression for the terminal velocity of a sphere falling vertically in a
viscous liquid.
11 In a car lift, compressed air exerts a force F1 on a small piston having a radius of 5 cm. This
pressure is transmitted to a second piston of radius 15 cm. Following figure illustrates the car lift.
If the mass of the car to be lifted is 1350 kg, what is F1? What is the pressure necessary to
accomplish this task?