200 Best MCQs on fluid flow- biochemical engineering
Q25). The viscosity of a fluid increases with increasing stirrer speed. This fluid would be best described as being
a).newtonian
b).pseudoplastic
c).dilatant
d).thixotropic
Correct Answer:
dilatant
Explaination:
Q26). A dilatant 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:
increases with increasing stirrer speed
Explaination:
Q27). A rheopectic 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 mixing time
d).decreases with mixing time
Correct Answer:
increases with mixing time
Explaination:
Q28). A fluid in which the viscosity increases with increasing stirrer speed and mixing time can be called as
a).newtonian fluid
b).pseudoplastic, thixotropic fluid
c).dilatant, rheopectic fluid
d).dilatant pseudoplastic fluid
Correct Answer:
dilatant, rheopectic fluid
Explaination:
Q29). The medium will have the highest viscosity (considering that the cells do not secrete gums) with the presence of
a).single celled bacteria
b).filamentous fungi that form pellets
c).filamentous fungi that grow as long poorly branched chains
d).yeast
Correct Answer:
filamentous fungi that grow as long poorly branched chains
Explaination:
Q30). A Newtonian 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:
is constant regardless of the stirrer speed or mixing time
Explaination:
Q31). Which pattern of mixing is preferred in stirred tank reactors during the culture of aerobic microorganisms?
a).Laminar flow
b).Transient flow
c).turbulent flow
d).all of these
Correct Answer:
turbulent flow
Explaination:
Q32). Animal cell cultures do not have much effect on shear forces because
a).the cell size is generally smaller than the critical eddy size at which shear will have an effect
b).cells are larger than the critical eddy size at which shear will have an effect
c).animal cells have cell walls
d).animal cells have cell membranes
Correct Answer:
the cell size is generally smaller than the critical eddy size at which shear will have an effect
Explaination: