Civil Engineering Hydraulics/Fluid Mechanics Mock test – 3 Welcome to your Hydraulics Mock test - 3 Take an exciting test in Hydraulics/Fluid Mechanics You have only 20 mins to complete the test (25 Questions) Wish you all the best!!! Name Email 1. Fluids change the volume under external presssure due to A. plasticity B. viscosity C. compressibility D. none of these.2. Most economical section of a triangular channel, is A. equilateral triangle B. right angled triangle C. isosceles triangle with 45° vertex angle D. right angled triangle with equal sides.3. Shear stress is directly proportional to A. the velocity B. the shear strain C. the viscosity D. the velocity.4. When no air is left below the nappe and water stream adheres to the down stream face of the weir, it is known as A. free nappe B. depressed nappe C. clinging nappe D. none of these.5. To avoid vapourisation, pipe lines are laid over the ridge so that these are above the hydraulic gradient line, not more than A. 2.4 m B. 6.4 m C. 10.0 m D. 5.0 m6. The rise of the liquid along the walls of a revolving cylinder above the initial level, is A. greater than the depression of the liquid at the axis of rotation B. lesser than the depression of the liquid at the axis of rotation C. the same as the depression of the liquid at the axis of rotation D. none of these.7. Cappoletti weir is a A. rectangular weir whose length is kept 3 times the height of the water above sill B. triangular weir whose notch angle is 90° C. trapezoidal weir, whose sides slope 1 horizontal to 2 verticals D. a combination of rectangular and triangular weirs.8. On an inclined plane, centre of pressure is located A. at the centroid B. above the centroid C. below the centroid D. anywhere.9. In an open tube, free surface of mercury remains A. horizontal B. curved upwards C. curved downwards D. none of these.10. For the flow of liquid from an open ended tube (or nozzle) leading to the formation of spray of liquid drops, the number generally applied, is A. Froude number B. Weber number C. Reynold number D. Mach number.11. Dimensions of the dynamic viscosity (μ) are A. MLT-2 B. M-1L-1T-1 C. ML-1T-2 D. ML-1T-1.12. The following is not a laminar flow A. Flow of oil in measuring instruments B. Flow in beds in ground water C. Rise of water in plants through roots D. Flow of blood in the arteries of human body E. Flow in water pipe lines.13. For exerting a pressure of 4.8 kg/cm2, the depth of oil (specific gravity 0.8), should be A. 40 cm B. 41 cm C. 56 cm D. 60 cm14. An error of 1% in measuring the head of water over the crest of a triangular notch, produces an error in the discharge which is equal to A. 1.25% B. 1.5% C. 2.0%. D. 2.5%15. Atmospheric pressure is equal to water column head of A. 9.81 m B. 5.0 m C. 10.30 m D. 7.5 m.16. Piezometers are used to measure A. pressure in water channels, pipes etc. B. difference in pressure at two points C. atmospheric pressure D. very low pressure.17. Uniform flow is said to occur when A. size and shape of the cross-section in a particular length remain constant B. size and shape of the cross-section change along a length C. frictional loss in the particular length of the channel will the more than the drop in its elevation D. frictional loss in the particular length of the channel, will be less than the drop in elevation.18. To avoid an interruption in the flow of a syphon, an air vessel is provided A. at the inlet B. at the outlet C. at the summit D. at any point between intet and outlet.19. f total head available at the inlet of pipe and f1 is the loss of head due to friction in the pipe, the maximum efficiency of transmission of power (ηmax) is A. 1/2 B. 2/3 C. 3/4 D. 4/520. Discharge over an ogee weir remains the same as that of A. sharp crested weir B. triangular weir C. cippoletti weir D. drowned weir.21. Molecules of fluids get attracted due to A. capillarity action B. surface tension C. adhesion D. cohesion22. The best side slope for most economical trapezoidal section, is A. 30° B. 45° C. 60° D. None of these.23. If velocities of fluid particles vary from point to point in magnitude and direction, as well as from instant to instant, the flow is said to be A. laminar B. turbulent flow C. uniform flow D. non-uniform flow.24. The value of momentum correction factor (β) for a laminar flow through a circular pipe, is A. 1/2 B. 2/3 C. 3/4 D. 4/3 E. 3/225. Manometers are used to measure A. pressure in water channels, pipes etc. B. difference in pressure at two points C. atmospheric pressure D. very low pressure.