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BIEN 501 Physiological Modeling
Question Bank
April 21, 2004
1. What is the primary difference between dynamic viscosity (µ) and kinematic viscosity
(ν)?
(a) Kinematic viscosity is independent of pressure.
(b) Dynamic viscosity is independent of temperature.
(c) Dynamic viscosity is independent of pressure.
(d) Kinematic viscosity is independent of temperature.
(e) None of the above.
2. If the dynamic viscosity of the fluid shown in the diagram is 0.001 N•s/m2, what is the
shear stress 0.25 m from the wall?
(a) Integrate the given equation and substitute the value for ‘y.’
(b) Differentiate the equation and apply Newton’s law of viscosity.
(c) Add both (a) & (b).
(d) Subtract (b) from (a)
(e) None of the above.
3. Which is true of a liquid?
(a) Its viscosity increases with temperature.
(b) The primary cause of its viscosity is momentum transfer by random molecular
motion.
(c) Its density is much lower than that of a gas.
(d) The primary cause of its viscosity is cohesion between adjacent molecules.
4. In the combined relation for shear stress which of the following is true for the term
dilatational viscosity (a) It is important in describing sound absorption in polyatomic gases.
(b) It is important in describing the fluid dynamics of liquids containing gas bubbles.
(c) It is equal to zero for monatomic gases.
(d) It is not considered for incompressible fluids as delV =0
(e) All of the above.
5. Which of the following represents the conditions for velocity distribution of a pure
rotating fluid?
(a) vx = -1/2bx, vy = 1/2by, vz = bz.
(b) vx = -by, vy = bx, vz =0.
(c) vx = by, vy = bx, vz =0.
(d) vx = bx, vy = by, vz =0.
(e) none of the above
6. In shell momentum balance, for all the boundary conditions it is presumed that there is
no?
(a) adsorption or absorption.
(b) dissolution or evaporation.
(c) melting or chemical reaction.
(d) all of the above.
(e) none of the above.
7. In the case of falling film problem when the film is nonisothermal, position dependent
viscosity is given by
(a) μ =μ0e (-αx/δ)
(b) μ =μ0e (-α/δx)
(c) μ =μ0/e (-αx/δ)
(d) μ =μ0e (-αx/δ)
(e) μ =μ0e(-δ /αx)
8. A cone plate viscometer, with cone radius ‘R’=10 cm and of aperture angle θ0=0.5 is to
be used to measure the viscosity of Newtonian solutions. What torque, in dyne-cm, will be
required to turn the cone at an angular velocity of 10 rad/min if the fluid viscosity is 100
c.p.?
(a) 4.0*10-4
(b) 3.85*104
(c) 40.0*103
(d) 5.6*103
(e) 3.6*102
9. In their limiting case, the graphs represented below would equal which of the
following fluid flows:
(a)
(b)
(c)
(d)
(e)
Velocity distribution.
Stokes flow.
Plane slit flow.
Hagen-Poiseuille.
Both b&c.
None of the above.
Shear stress or momentum flux distribution.
10.In creeping flow around a sphere total force F of the fluid on the sphere is given by
which of these sums?
(a) Buoyant force and kinetic force.
(b) Buoyant force, form drag and friction drag.
(c) Buoyant force and friction drag only.
(d) Both a & b.
(e) None of the above.
11. Which of the following is called equation of continuity?
(a)
(b)
(c)
(d)
(e)

    V 
t
 1 
rv r   1  v    v z   0

t r r
r 
z
 1 
rv r   1  v sin    1  v   0
 2
t r r
r sin  
r sin  
 


 v x   v y   v z   0
t x
y
z
All of the above.
12. Which of these is a consequence of the equation of change of mechanical energy?
(a) Navier-Stokes equation.
(b) Hagen-Poiseuille.
(c) Angular momentum.
(d) Bernoulli’s Equation.
(e) None of the above.
13. Which of the following simplifications of equations of motion leads to stokes flow?
(a) Keeping density and viscosity of the fluid constant.
(b) Neglecting viscous forces.
(c) Neglecting acceleration terms.
(d) Both a and c.
(e) None of the above.
14. Consider a Cell culture medium. The equation representing the flow of fluid in this is
(a) Hyperbola.
(b) Parabola.
(c) Elliptical.
(d) Asymptotic.
(e) None of the above.
15. What is the importance of dimensionless quantities in the analysis of the equations of
change?
(a) Is that they reduce calculations.
(b) They help in scaling ratios of all dimensions in original systems to scaled-up or
scaled- down systems.
(c) Their magnitude gives an indication of the relative importance of inertial and
viscous forces in the fluid system.
(d) Both c &d.
(e) None of the above.
16. Which of this equation represents the equation for stream function?
 2
  ,  2
(a)
 
 v 4
t
x, y 

 

 

 

 2
  ,  2
(b)
 
 v 3
y
x, y 

 2
  ,  2
 
 v 4
x
x, y 
(d) All the above.
(e) None of the above.
(c)

17. Solving for the potential equations for the far field and ______________equations for
the near field and then matching the solutions ____________ for large Re, an
understanding of the entire flow field around a streamlined object.
(a) Large field, parabolically
(b) Large field, linearly
(c) Near field, linearly
(d) Near field, asymptotically
 z R
18.Find out the stream function of the following potential: w( z )  v R  
R z

R2 y 

(a)  x, y   v  y  2
x  y 2 


x2 

(b)  x, y   v y1  2
2 
 x y 
 x2  y2 

(c)  x, y   v y1 
R 2 


R2 


(d)  x, y   v 1  2
2 
x

y


hint: variable separable method for solving partial differentials.
19.The hydraulic mean diameter of the annular space between pipes of diameters 0.4m
and 0.6m is ______.
(a) 0.189 m
(b) 0.2 m
(c) 0.213 m.
(d) 0.97 m.
(e) none of the above.
20.For an ideal fluid flow the Reynolds number is(a) infinity
(b) zero
(c) one
(d) 2100
(e) none of the above.