171. With increase in pump speed, its NPSH requirement
Decreases
Increases
Remains unaltered
Can either increase or decrease ; depends on other factors
✅ The correct answer is option B.
Fluid Mechanics MCQs
172. For the free settling of a spherical particle through a fluid, the slope of, CD-log NRe , plot is
1
-1
0.5
-0.5
✅ The correct answer is option B.
173. When the momentum of one fluid is used for moving another fluid, such a device is called a/an
Jet pump
Blower
Acid egg
None of these
✅ The correct answer is option A.
174. Weber number is the ratio of inertial force to __________ force.
Surface tension
Gravity
Viscous
Elastic
✅ The correct answer is option A.
175. For water, when the pressure increases, the viscosity
Also increases
Decreases
Remains constant
First decreases, and then increases
✅ The correct answer is option D.
176. For pipes that must be broken at intervals for maintenance, the connector used should be a/an
Union
Tee
Reducer
Elbow
✅ The correct answer is option A.
177. The ratio of inertial forces to gravity forces is called the __________ number.
Mach
Froude
Euler
Weber
✅ The correct answer is option B.
178. Boundary layer exists in flow
Of real fluids
Over flat surfaces only
In pipes only
Of ideal fluids only
✅ The correct answer is option A.
179. Specific speed of a centrifugal pump relates it with another pump having the
Dynamic similarity
Same efficiency
Same speed
Geometrical similarity
✅ The correct answer is option A.
180. The component of acceleration resulting due to unsteady nature of flow is called __________ acceleration.
Normal
Local
Convective
Tangential
✅ The correct answer is option B.