Deck 8: External Flows

Question 1

If kinetic energy is desired, the variable $$\eta \text { in Eq. } 4.2 .6$$ in Eq. 4.2.6 would be represented by: (A) $V$
(B) $V ^ { 2 }$
(C) $V ^ { 2 } / 2$
(D) $m V ^ { 2 } / 2$

Answer 1

C
$V ^ { 2 } / 2$
$\text {Kinetic energy is \(m V ^ { 2 } / 2\) so the kinetic energy of an infinitesimal mass is \(\frac { 1 } { 2 } \rho V ^ { 2 } d V\)}$

Question 2

Which property listed below is an intensive property?
(A) Internal energy
(B) Mass
(C) Density
(D) Enthalpy

Answer 2

WHICH PROPERTY LISTED BELOW IS AN INTENSIVE PROPERTY?
(C) Density
Density does not depend on the amount of mass in a system.

Question 3

Which quantity listed below is an integral quantity?
(A) Velocity
(B) Pressure
(C) Temperature
(D) Mass

Answer 3

WHICH QUANTITY LISTED BELOW IS AN INTEGRAL QUANTITY?
(D) Mass
To find mass the density is integrated over a volume.

Question 4

$$\text { For a fixed control volume, the reason why } \frac { d } { d t } \int _ { \text {c.. } } \rho \eta d V = \int _ { \text {c. } . } \frac { \partial } { \partial t } ( \rho \eta ) d V \text { is: }$$

A) The integrand is independent of time
B) The limits of integration are independent of time
C) The flow is a steady flow
D) The quantity ρη is independent of position

Question 5

$$\text { If the control volume equation for a flow is } \eta _ { 2 } \rho _ { 2 } A _ { 2 } V _ { 2 } = \eta _ { 1 } \rho _ { 1 } A _ { 1 } V _ { 1 } \text {, the flow may be: }$$

A) Uniform flow into and from a fixed volume
B) Steady, uniform flow in a pipe
C) Uniform flow in a conduit
D) Steady, one-dimensional flow in a channel