Fluid Mechanics

521.The length of the tube necessary for the boundary layer to reach the centre of the tube and for fully developed flow to be established is called the _________ length.

  1. Equivalent
  2. Transition
  3. Prandtl mixing
  4. None of these
Correct answer: (B)
Transition

522.The lift of a balloon is

  1. Increased, as it rises to a higher altitude
  2. Due to the weight of the atmospheric air, that it displaces
  3. Not dependent on the temperature of the atmosphere
  4. None of these
Correct answer: (B)
Due to the weight of the atmospheric air, that it displaces

523.The line of action of the buoyant force acts through the

  1. Centroid of the displaced volume of fluid
  2. Centre of gravity of a submerged body
  3. Centroid of the volume of any floating body
  4. None of these
Correct answer: (A)
Centroid of the displaced volume of fluid

524.The line of action of the buoyant force passes through the centre of gravity of the

  1. Submerged body
  2. Displaced volume of the fluid
  3. Volume of fluid vertically above the body
  4. Horizontal projection of the body
Correct answer: (B)
Displaced volume of the fluid

525.The line traced by a single fluid particle as it moves over a period of time is called _________ line.

  1. Stream
  2. Path
  3. Equipotential
  4. None of these
Correct answer: (B)
Path

526.The location of centre of pressure, which defines the point of application of the total pressure force on the surface, can be calculated by applying the principle of moments according to which "sum of the moment of the resultant force about an axis is equal to the sum of the components about the same axis". The centre of pressure of a rectangular surface (of width 'w') immersed vertically in a static mass of fluid is at a depth of (where, y = depth of the liquid)

  1. 1/(y/3)
  2. 2y/3
  3. 1/(y/4)
  4. 3y/4
Correct answer: (B)
2y/3

527.The losses in open channel flow generally vary as the

  1. Inverse of the roughness
  2. First power of the roughness
  3. Square of the velocity
  4. Inverse square of hydraulic radius
Correct answer: (B)
First power of the roughness

528.The Mach number for hypersonic flow of compressible fluid is

  1. 1
  2. > 1
  3. > 4
  4. < 2
Correct answer: (C)
> 4

529.The main factor on which the behaviour of a mass of fluidised solid depends mainly is the

  1. Fluid characteristics
  2. Particle size
  3. Both (A) and (B)
  4. Neither (A) nor (B)
Correct answer: (C)
Both (A) and (B)

530.The maximum delivery pressure of a reciprocating compressor may be about _________ kg/cm2.

  1. 1000
  2. 2000
  3. 3000
  4. 4000
Correct answer: (D)
4000
Previous
Page 53 of 73
Next
Copyright © EngineeringMCQ.com