Fluid Mechanism BHEL Trainee Engineers Exam

Fluid Mechanism BHEL Trainee Engineers Exam
 Geology Science Practice Entrance Paper

Q.1 Surface tension

(a) Acts in the plane of interface normal to any

line in the surface

(b) Is also known as capillarity

(c) Is a function ofthe curvature of the interface

(d) Decreases with fall in temperature

ANSWER: (d)

Q.2.The purpose of surge tank in a pipe line is to

(a) Smoothen the flow of water

(b) Minimise friction losses in pipe

(c) Prevent occurrence of hydraulic jump

(d) Relieve pressure due to water hammer

ANSWER: (b)

Q.3. Unsteady uniform flow is flow through

(a) An expanding tube at an increasing rate

(b) An expanding tube at constant rate

(c) A long pipe at decreasing rate

(d) A long pipe at constant rate

ANSWER: (d)

Q.4. A balloon lifting in air follows the

(a) Law of gravitation

(b) Archimedes principle

(c) Principle of buoyancy

(d) All of the above

 ANSWER: (b)

Q.5. Viscosity of water in comparison to mercury is

(a) Higher

(b) Lower

(c) Same

(d) Unpredictable

ANSWER: (a)

Q.6. Water enters a turbine at 900 kPa will negligible

velocity, the maximum speed in m/s, it can reach before

it enters the turbine rotor will be

(a) 52

(b) 47

(c) 45

(d) 4.2

ANSWER: (c)

Q.7. The shear stress in a turbulent pipe flow

(a) Varies parabolically with radius

(b) Is constant over the pipe radius

(c) Varies according to 1/7 th power law

(d) Is zero at the centre and increased linearly to

the wall

ANSWER: (d)

Q.8. The generating capacity of world’s largest

capacity hydroelectric plant is of the order or

(a) 2000 MW

(b) 3000 MW

(c) 4000 MW

(d) 5000MW

ANSWER: (d)

Q.9. The turbine that cannot be installed in high plant is

(a) Peloton wheel, horizontal

(b) Peloton wheel, vertical

(c) Francis turbine, horizontal

(d) Kaplan turbine

ANSWER: (d)

Q.10. When the relationship between Reynolds

number and the friction factor is represented

by a straight line, the flow is said to be

(a) Isentropic

(b) Laminar

(c) Turbulent

(d) Vortex

ANSWER: (b)

Q.11. Most economical section of a triangular channel

is an isosceles triangle with vertex angle of

(a) 30°

(b) 45°

(c) 60°

(d) 90°

ANSWER: (d)

Q.12. The line traced by a single fluid particle as it

moves over a period of time is called

(a) Line of force

(b) Filament line

(c) Flow line

(d) Path line

ANSWER: (d)

Q.13. A hot wire anemometer is used for the

measurement of

(a) Pressure of gases

(b) Velocity of gases

(c) Viscosity of gases

(d) Viscosity of liquids

ANSWER: (b)

Q.14. Drag force on a 40 : 1 scale model of a ship is

measured to be 10N Force expected on the ship will be

(a) 640 kN

(b) 520 kN

(c) 320 kN  

(d) 80 kN

ANSWER: (a)

Q.15. Hydraulic grade line as compared to the centre

line of conduit

(a) Should always above

(b) Should always below

(c) Should always the parallel

(d) May be above or below

ANSWER: (a)

Q.16. Speed of a submarine can be measured by

(a) Pitot tube

(b) Hot wire anemometer

(c) Pirani gauge

(d) Inclined manometer

ANSWER: (c)

Q.17. The viscosity of a fluid varies with

(a) Temperature

(b) Temperature and pressure

(c) Pressure

(d) Density

ANSWER: (a)

Q.18. Portion of the power canal that extends from

intake works to power house, is known as

(a) Lead race

(b) Main storage

(c) Diversion canal

(d) Head race

ANSWER: (d)

Q.19. A fluid is a substance that

(a) Is essentially incompressible

(b) Always moves when subjected to a shearing stress

(c) Has a viscosity that always increases with temperature

(d) Has a viscosity that always decreases withtemperature

ANSWER: (b)

Q.20. A pyrometer cannot be used for pressure

measurement in pipes when

(a) Pressure difference is low

(b) Velocity is high

(c) Fluid in the pipe is a gas

(d) Fluid is highly viscous

ANSWER: (c)

Q.21. The pressure in meters of oil (specific gravity

0. 85) equivalent to 42.5 m of water is

(a) 42.5m

(b) 50m

(c) 52.5m

(d) 85m

 ANSWER: (b)

Q.22. For a given cross-section area, most economical

channel section has maximum

(a) Velocity of fluid

(b) Discharge

(c) Depth of fluid flowing

(d) Wetted perimeter

ANSWER: (b)

Q.23. The pressure inside a 4 cm diameter hose is 700

kPA. lf the water exits through a 2 cm diameter nozzle,

what velocity, in m/s, can be expected inside the hose ?

(a) 20.4

(b) 16.3

(c) 12.4

(d) 9.7

ANSWER: (d)

Q.24. A vessel containing water moves downward with

a constant acceleration equal to ‘g’, then

(a) The liquid mass will be in turbulence

(b) The liquid mass will be under a pressure below the atmospheric pressure

(c) The liquid mass will be under a pressure double the atmospheric pressure

(d) The pressure throughout the liquid mass will be atmospheric

ANSWER: (d)

Q.25. Friction drag is generally larger than the pressure drag in

(a) Flow past a sphere

(b) Flow past a cylinder

(c) Flow past an airfoil

(d) Flow past a thin sheet.

ANSWER: (b)