fluid mech

Question 1

A branch of Mechanics
which focuses on the behavior of fluids at rest or in motion,
and the interaction of fluids with solids or
other fluids at the boundaries.

Answer 1

Fluid Mechanic

Question 2

Studies the motion of
incompressible fluids

Answer 2

Hydrodynamics

Question 3

a subcategory of hydrodynamics
that deals with liquid flows within pipes and
open channels.

Answer 3

Hydraulics

Question 4

deals with the flow of fluids
that undergo significant density changes,
such as the flow of gases through nozzles at
high speeds.

Answer 4

Gas Dynamics

Question 5

is the force per unit area
determined by dividing the force by the
area upon which it acts

Answer 5

stress

Question 6

refers to the normal
component of a force acting on a surface
per unit area

Answer 6

normal stress

Question 7

is the tangential component
of a force acting on a surface per unit
area

Answer 7

shear stress

Question 8

the normal stress
experienced by a fluid at rest

Answer 8

pressure

Question 9

The vapor phase of a substance is
customarily called ____ when it is
above the critical temperature

Answer 9

A gas

Question 10

implies that the current phase is
not far from a state of condensation.

Answer 10

vapor

Question 11

flow region adjacent to
the wall in which the viscous effects (and
thus the velocity gradients) are significant

Answer 11

Boundary Layer

Question 12

the force a fluid exerts on a surface in the flow
direction

Answer 12

Surface drag or skin friction drag

Question 13

fluid and a solid surface have the same
temperature at the points of contact

Answer 13

no-temperature-jump condition

Question 14

is a measure of internal stickiness of the
fluid caused by cohesive forces between the
molecules in liquids and by molecular collision in
gases.

Answer 14

Viscosity

Question 15

Flows in which the frictional
effects are significant

Answer 15

Viscous flows

Question 16

regions (typically regions
not close to solid surfaces) where viscous forces
are negligibly small compared to inertial or
pressure forces

Answer 16

Inviscid flow regions

Question 17

The flow of an unbounded fluid
over a surface such as a plate, a wire, or a pipe;
viscous effects are limited to boundary layers
near solid surfaces and to wake regions
downstream of bodies.

Answer 17

External flow

Question 18

fluid is bounded by solid
surfaces; dominated by viscous effects
throughout the flow fields.

Answer 18

Internal flow

Question 19

flow of liquids in a duct that
is only partially filled with the liquid, forming a free
surface.

Answer 19

Open-channel flow

Question 20

the density remains
nearly constant throughout; the volume of
every portion of fluid remains unchanged over
the course of its motion

Answer 20

Incompressible flow

Question 21

a dimensionless number
used to approximate and model gas flows as
incompressible

Answer 21

Mach number

Question 22

the highly ordered fluid motion
characterized by smooth layers of fluid; e.g., The
flow of high-viscosity fluids such as oils at low
velocities

Answer 22

Laminar flow

Question 23

the disordered fluid motion
typically occurring at high velocities and
characterized by velocity fluctuations; the flow of
low-viscosity fluids such as air at high velocities

Answer 23

Turbulent flow

Question 24

a flow that alternates
between being laminar and turbulent.

Answer 24

Transitional flow

Question 25

is the key parameter for the
determination of the flow regime in pipes

Answer 25

Reynolds Number

Question 26

if a fluid is forced to flow over a
surface or in a pipe by external means such as
a pump or a fan.

Answer 26

Forced flow

Question 27

fluid motion is due to natural
means such as the buoyancy effect, which
manifests itself as the rise of warmer (and thus
lighter) fluid and the fall of cooler (and thus
denser) fluid.

Answer 27

Natural flow

Question 28

can be closely approximated by
devices that are intended for continuous operation

Answer 28

can be closely approximated by
devices that are intended for continuous operation

Question 29

states that the net heat energy supplied to the system is equal to sum of change in internal energy of the system and work done by the system. This means that heat energy cannot be created or destroyed.

Answer 29

first law of thermodynamics

Question 30

any device that will have a continuous flow of material through it. Some examples of steady flow devices include pipes, nozzles, diffusers, and pumps. Generally the material flowing through the device is a gas or liquid, and if the device in any way changes the velocity of the fluid then that fluid will exert a force

Answer 30

steady flow device

Question 31

can exchange both energy and matter with its surroundings.

Answer 31

open system