Engineering Questions with Answers - Multiple Choice Questions
Mechanical Operations MCQ’s – Classification of Solid Particles
1 - Question
The underflow ratio is defined as ___
a) D/E
b) B/F
c) E/F
d) D/F
View Answer
Answer: b
Explanation: The overflow ratio is defined as the ratio of mass flow rate F and the mass flow rate of underflow i.e. D, so D/F.
2 - Question
Calculate the overflow ratio, if the mass fraction in feed is 0.635 and fraction in overflow is 0.945, while in underflow is 0.285?
a) 0.85
b) 0.66
c) 0.75
d) 0.50
View Answer
Answer: b
Explanation: As D/F = Xf –Xd/Xd – Xb = (0.635 – 0.285)/ (0.945 – 0.285) = 0.66.
3 - Question
Calculate the underflow, if overflow is given as 0.45?
a) 0.34
b) 0.55
c) 0.33
d) 0.55
View Answer
Answer: a
Explanation: As B/F = 1- (D/F) = 1 -0.45 = 0.55.
4 - Question
The effectiveness E can be defined as ____
a) FXD/ BXD
b) BXD/FXF
c) DXD/FXF
d) BXD/ DXF
View Answer
Answer: c
Explanation: The screen effectiveness E = DXD/FXF, which is the ratio of oversized material in overflow and the amount that entering in the feed.
5 - Question
Calculate E, if the D/F ratio is 1.2 and amount of overflow and feed is 0.33 and 0.45?
a) 0.85
b) 0.55
c) 0.88
d) 0.80
View Answer
Answer: c
Explanation: As we know E = E = DXD/FXF = 1.33 (0.33/0.45) = 0.88.
6 - Question
Separation of a solid from suspension in liquid by screen means is called as _____
a) Sedimentation
b) Extraction
c) Distillation
d) Leaching
View Answer
Answer: a
Explanation: The separation of solids from a suspension in liquid by means of porous medium or screen which retains the solids and allows the liquid to pass is known as filtration.
7 - Question
Which of the following is not a driving force used for filtration?
a) Gravity
b) Atmospheric pressure
c) Centrifugal force
d) Drag force
View Answer
Answer: d
Explanation: Drag force cannot be implied for separation technique that used in filtration, filtrate is forced through porous medium by gravity, super atmospheric pressure or downstream centrifugal force.
8 - Question
Filter medium filtration is also called ____
a) Locking
b) Blocking
c) Chapping
d) Chipping
View Answer
Answer: b
Explanation: The mechanism in which the solids are trapped within the pores of medium leads to the filter medium filtration also called as blocking.
9 - Question
The properties like viscosity, density, corrosion are important while selecting equipment’s.
a) False
b) True
View Answer
Answer: a
Explanation: The properties like viscosity, density, corrosion and also shape, size distribution and packing are important while selecting equipment’s.
10 - Question
If the filtration pressure is constant, the rate of flow will _____
a) Increase
b) Diminish
c) Stop
d) Be constant
View Answer
Answer: b
Explanation: If the filtration pressure is constant, the rate of flow will progressively diminish, whereas if flow rate is to be maintained constant.