200 Best MCQs on fluid flow- biochemical engineering
Q9). A pseudoplastic fluid is one in which the viscosity
a).is constant regardless of the stirrer speed or mixing time
b).changes during mixing but returns to its original state after mixing
c).increases with increasing stirrer speed
d).decreases with increasing stirrer speed
Correct Answer:
decreases with increasing stirrer speed
Explaination:
Q10). A viscoelastic fluid is one in which the viscosity
a).is constant regardless of the stirrer speed or mixing time
b).changes during mixing but returns to its original state after mixing
c).increases with increasing stirrer speed
d).decreases with increasing stirrer speed
Correct Answer:
changes during mixing but returns to its original state after mixing
Explaination:
Q11). Mixing in stirred tank reactors can
a).be described as either laminar, transient or turbulent
b).achieve turbulent conditions by increasing the stirrer speed
c).induce laminar flow conditions by the addition of baffles
d).all of the above
Correct Answer:
be described as either laminar, transient or turbulent
Explaination:
Q12). In animal cell bioreactor, bubble damage can be minimized by
a).the addition of a shear protectorant
b).using a bubble free oxygen delivery system
c).headspace aeration
d).all of the above
Correct Answer:
all of the above
Explaination:
Q13). The viscosity of a fluid changes with either stirrer speed or mixing time. But when mixing ceases, the viscosity returns to its original state. This fluid is best described as
a).newtonian
b).rheopectic
c).viscoelastic
d).thixotropic
Correct Answer:
viscoelastic
Explaination:
Q14). In sparged mammalian cell bioreactors, the cell damage is caused because of
a).shear stress arising during mixing of the cell culture fluid
b).shear stresses arising from the breakup of bubbles at the liquid surface
c).shear stresses between bubbles in foam at the liquid surface
d).all of the above
Correct Answer:
shear stress arising during mixing of the cell culture fluid
Explaination:
Q15). The viscous nature of a non-Newtonian fluid
a).remains constant with time and power input
b).changes with the level of power input and/or the length of time during which the fluid is mixed
c).is similar to that of a perfect gas
d).is similar to that of water
Correct Answer:
changes with the level of power input and/or the length of time during which the fluid is mixed
Explaination:
Q16). Which of the following compound, if added to a solution will lead to the greatest increase in viscosity?
a).A globular protein
b).Glucose
c).A long chain protein such as albumin
d).Water
Correct Answer:
A long chain protein such as albumin
Explaination: