Hydraulics And Fluid Mechanics MCQ

Test your knowledge with important Hydraulics And Fluid Mechanics MCQ and their applications. These MCQs are beneficial for competitive exams too. Explore 30 + more Hydraulics And Fluid Mechanics MCQs at Bissoy

• Metacentric height for small values of angle of heel is the distance between the
  ক

  centre of gravity and centre of buoy-ancy

  খ

  centre of gravity and metacentre

  গ

  centre of buoyancy and metacentre

  ঘ

  free surface and centre of buoyancy
• A floating body is said to be in a state of stable equilibrium
  ক

  when its metacentric height is zero

  খ

  when the metacentre is above the centre of gravity

  গ

  when the metacentre is below the centre of gravity

  ঘ

  only when its centre of gravity is below its centre of buoyancy
• A rectangular block 2 m long, 1 m wide and 1 m deep floats in water, the depth of immersion being 0.5 m. If water weighs 10 kN/m³, then the weight of the block is
  ক

  5 kN

  খ

  10 kN

  গ

  15 kN

  ঘ

  20 kN
• A square surface 3 m x 3 m lies in a vertical line in water pipe its upper edge at vater surface. The hydrostatic force on square surface is
  ক

  9,000 kg

  খ

  13,500 kg

  গ

  18,000 kg

  ঘ

  27,000 kg
• The rise or depression of liquid in a tube due to surface tension wim increase in size of tube will
  ক

  increase

  খ

  remain unaffected

  গ

  may increase or decrease depending on the characteristics of liquid

  ঘ

  decrease
• Coefficient of discharge for a totally submerged orifice as compared to that for an orifice discharging free is
  ক

  slightly less

  খ

  slightly more

  গ

  nearly half

  ঘ

  equal
• Differential monometer is used to measure
  ক

  pressure in pipes, channels etc

  খ

  atmospheric pressure

  গ

  very low pressure

  ঘ

  difference of pressure between two points
• The pitot tube is used to measure
  ক

  velocity at stagnation point

  খ

  stagnation pressure

  গ

  static pressure

  ঘ

  dynamic pressure
• A piece of metal of specific gravity 7 floats in mercury of specific gravity 13.6. What fraction of its volume is under mercury ?
  ক

  0.5

  খ

  0.4

  গ

  0.515

  ঘ

  0.5
• The distance y from pipe boundary, at which the point velocity is equal to average velocity for turbulent flow, is (where R is radius of pipe)
  ক

  0.223 R

  খ

  0.423 R

  গ

  0.577 R

  ঘ

  0.707 R
• The velocity of jet of water travelling out of opening in a tank filled with water is proportional to
  ক

  Head of water (h)

  খ

  h²

  গ

  V/T

  ঘ

  h/2
• The speed of sound in a ideal gas varies directly as its
  ক

  absolute temperature

  খ

  temperature

  গ

  density

  ঘ

  modulus of elasticity
• Which of the following is an incorrect statement ?
  ক

  Coefficient of contraction of a venturimeter is unity

  খ

  Flow nozzle is cheaper than venturimeter but has higher energy loss

  গ

  Discharge is independent of orientation of venturimeter whether it is horizontal, vertical or inclined

  ঘ

  None of the above statement is incorrect
• Which of the following instruments is used to measure flow on the application of Bernoulli’s theorem
  ক

  Venturimeter

  খ

  Orifice plate

  গ

  pitot tube

  ঘ

  all of the above
• Units of surface tension are
  ক

  energy/unit area

  খ

  distance

  গ

  both of the above

  ঘ

  it has no units
• If the velocity is zero over half of the cross-sectional area and is uniform over the remaining half, then the momentum correction factor is
  ক

  1

  খ

  $$\frac{4}{3}$$

  গ

  2

  ঘ

  4
• The value of mass density in kg.sec²m⁴ for water at 0°C is
  ক

  1

  খ

  1000

  গ

  100

  ঘ

  101.9
• Total pressure on a 1m × 1m gate immersed vertically at a depth of 2 m below the free water surface will be
  ক

  1000 kg

  খ

  4000 kg

  গ

  2000 kg

  ঘ

  2500 kg
• Size of a venturimeter is specified by
  ক

  pipe diameter

  খ

  throat diameter

  গ

  angle of diverging section

  ঘ

  both pipe diameter as well as throat diameter
• When the velocity distribution is uniform over the cross-section, the correction factor for momentum is
  ক

  0

  খ

  1

  গ

  $$\frac{4}{3}$$

  ঘ

  2
• The speed of a pressure wave through a pipe depends upon
  ক

  the length of pipe

  খ

  the viscosity of fluid

  গ

  the bulk modulus for the fluid

  ঘ

  the original head
• The maximum thickness of boundary layer in a pipe of radius r is
  ক

  0

  খ

  $$\frac{{\text{r}}}{2}$$

  গ

  r

  ঘ

  2r
• The depth of the center of pressure on a vertical rectangular gate 8 m wide and 6 m high, when the water surface coincides with the top of the gate, is
  ক

  2.4 m

  খ

  3.0 m

  গ

  4.0 m

  ঘ

  2.5 m
• For pipes, laminar flow occurs when Roynolds number is
  ক

  less than 2000

  খ

  between 2000 and 4000

  গ

  more than 4000

  ঘ

  less than 4000
• Which of the following instrument can be used for measuring speed of a submarine moving in deep sea
  ক

  Venturimeter

  খ

  hot wire anemometer

  গ

  rotameter

  ঘ

  pitot tube
• The losses are more in
  ক

  laminar flow

  খ

  transition flow

  গ

  turbulent flow

  ঘ

  critical flow
• In steady flow of a fluid, the total accele ration of any fluid particle
  ক

  can be zero

  খ

  is never zero

  গ

  is always zero

  ঘ

  is independent of coordinates
• A closed tank containing water is moving in a horizontal direction along a straight line at a constant speed. The tank also contains a steel ball and a bubble of air. If the tank is decelerated horizontally, then<br>i) the ball will move to the front<br>ii) the bubble will move to the front<br>iii) the ball will move to the rear<br>iv) the bubble will move to the rear <br>Find out which of the above statements are correct ?
  ক

  (i) and (ii)

  খ

  (i) and (iv)

  গ

  (ii) and (iii)

  ঘ

  (iii) and (iv)
• Stanton diagram is a
  ক

  log-log plot of friction factor against Reynolds number

  খ

  log-log plot of relative roughness against Reynolds number

  গ

  semi-log plot of friction factor against Reynolds number

  ঘ

  semi-log plot of friction factor against relative roughness
• A right circular cylinder open at the top is filled with liquid and rotated about its vertical axis at such a speed that half the liquid spills out, then the pressure intensity at the center of bottom is
  ক

  zero

  খ

  one-fourth its value when cylinder was full

  গ

  one-half its value when cylinder was full

  ঘ

  cannot be predicted from the given data