# Fluid Mechanics 17

Mechanical Engineering MCQ Question Papers: DRDO, ISRO, Interview

Subject: Fluid Mechanics 17

Part 5: List for questions and answers of Fluid Mechanics

Q1. In a forced vortex, the velocity of flow everywhere within the fluid is
a) Maximum
b) Minimum
c) Zero
d) Nonzero finite

Q2. A fluid which obeys the Newton’s law of viscosity is termed as
a) Real fluid
b) Ideal fluid
c) Newtonian fluid
d) Non-Newtonian fluid

Q3. In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than
a) Frictional force
b) Viscosity
c) Surface friction
d) All of the above

Q4. The value of coefficient of velocity for a sharp edged orifice __________ with the head
of water
a) Decreases
b) Increases
c) Remain same
d) None of these

Q5. The ratio of the inertia force to the __________ is called Euler’s number
a) Pressure force
b) Elastic force
c) Surface tension force
d) Viscous force

Q6. A one dimensional flow is one which
a) Is uniform flow
c) Takes place in straight lines
d) Involves zero transverse component of flow

Q7. An opening in the side of a tank or vessel such that the liquid surface with the tank is below the top edge of the opening, is called
a) Weir
b) Notch
c) Orifice
d) None of these

Q8. The property of fluid by virtue of which it offers resistance to shear is called
a) Surface tension
d) Viscosity

Q9. The mass of 2.5 m3 of a certain liquid is 2 tonnes. Its mass density is
a) 200 kg/m^3
b) 400 kg/m^3
c) 600 kg/m^3
d) 800 kg/m^3

Q10. A flow through an expanding tube at constant rate is called

Q11. Practical fluids
a) Are viscous
b) Possess surface tension
c) Are compressible
d) Possess all the above properties

Q12. The tendency of a liquid surface to contract is due to the following property
a) Cohesion
c) Viscosity
d) Surface tension

Q13. The Newton’s law of resistance is based on the assumption that the
a) Planes of the body are completely smooth
b) Space around the body is completely filled with the fluid
c) Fluid particles do not exert any influence on one another
d) All of the above

Q14. The flow in a pipe is neither laminar nor turbulent when Reynold’s number is
a) Less than 2000
b) Between 2000 and 2800
c) More than 2800
d) None of these

Q15. Stoke is the unit of
a) Kinematic viscosity in C. G. S. Units
b) Kinematic viscosity in M. K. S. Units
c) Dynamic viscosity in M. K. S. Units
d) Dynamic viscosity in S. I. Units

Q16. The vapour pressure over the concave surface is
a) Less man the vapour pressure over the plane surface
b) Equal to the vapour pressure over the plane surface
c) Greater than the vapour pressure over the plane surface
d) Zero

Q17. The velocity at which the flow changes from laminar flow to turbulent flow is called
a) Critical velocity
b) Velocity of approach
c) Sub-sonic velocity
d) Super-sonic velocity

Q18. Mercury is often used in barometer because
a) It is the best liquid
b) The height of barometer will be less
c) Its vapour pressure is so low that it may be neglected
d) Both (B) and (C)

Q19. Center of pressure compared to e.g. Is
a) Above it
b) Below it
c) At same point
d) Above or below depending on area of body

Part 5: List for questions and answers of Fluid Mechanics