1. What does the following represents?
Y = 1- e-ct
b) Fraction of samples
c) Mixing form
d) Can’t be specified
Answer: b [Reason:] If Y is the fraction of the samples containing the two materials in approximately the proportion in the whole mix.
2. What is the speed of an impact wheel?
a) 1750 rpm
b) 3500 rpm
c) 1750 or 3500 rpm
d) Can’t be predicted
Answer: c [Reason:] These disc turn at 1750 rpm for easy materials and 3500 rpm for materials that are hard to mix.
3. For a completely random mixture, the following equation gives ________
a) Mean deviation
b) Mean path
c) Standard path
d) Standard deviation
Answer: d [Reason:] This equation implies for any given size of spot sample there is a theoretical standard deviation for a completely random mixture.
4. What does the below equation represent?
a) Rate of increase
b) Rate of mixing
c) Rate of decrease
d) Rate constant
Answer: b [Reason:] It is found that for short mixing times, the rate of change if Is is a measure of how far mixing proceed towards equilibrium.
5. Fine powders that have flow characteristics, when agitated tend to ________
Answer: a [Reason:] Fine powders, that have flow characteristics similar to a liquid when agitated, tend to settle to a very difficult flow condition when settled.
6. Bulk solids can be stored either _________
c) Loose or Stacked
d) Not specific orientation
Answer: c [Reason:] Bulk solids can be stored either loose or contained. Loose storage is mainly held in stockpiles, but since stockpiles are rather infrequent in Chemical Engineering.
7. Any bulk solid is made up of _________
c) Two or more
d) Three or more
Answer: c [Reason:] Any bulk solid is made up of two or more phases, the most prominent of which is the disperse solids phase, the other phases are the interstitial fluid.
8. The elongation factor is given as ________
Answer: a [Reason:] If we assume that a and b are the sides of this smallest rectangle, A is the actual projected area then, the elongation factor is a/b.
9. The bulkiness is given as
Answer: b [Reason:] A is the actual projected area of the inscribed profile and U is its actual perimeter, than the bulkiness is given as A/a.b.
10. If the fluid passes upwards, then pressure drop is _________
d) Can’t be specified
Answer: c [Reason:] If the fluid passes upwards through the bed, the pressure drop will be same as for downward flow at low rates.