Engineering Questions with Answers - Multiple Choice Questions
Food Engineering MCQ’s – Unit Operations – Size Reduction and Seperation-1
1 - Question
Which of the following is an advantage of size reduction?
a) Enhanced heat/mass transfer
b) Intimate contact with certain food items
c) Enhanced heat/mass transfer & intimate contact with certain food items
d) None of the mentioned
View Answer
Explanation: Increased surface area due to size reduction enhances heat/mass transfer. Small sized particles have more intimate contact with certain food items.
2 - Question
Statement 1: Dispersion of one immiscible liquid into another also involves size reduction.
Statement 2: Leaching requires size reduction.
a) True, False
b) True, True
c) False, False
d) False, True
View Answer
Explanation: Dispersion of one immiscible liquid into another also involves size reduction so that they mix well. Leaching requires size reduction as it is desirable to access the interior parts of the particles which are enhanced by reducing the size of the particles.
3 - Question
Which of the following is NOT true with respect to size reduction?
a) Size reduction is an energy inefficient process as the energy required for grinding is very high
b) Some of the energy liberated in the formation of new small surfaces is the grinding energy required by food material per unit surface area to form new surface areas and the rest is generally just heat
c) The crushing efficiency is inversely proportional to the surface created
d) None of the mentioned
View Answer
Explanation: The crushing efficiency is directly proportional to the surface created
4 - Question
Which of the following is NOT a method used for size reduction?
a) Cutting
b) Impact
c) Burning
d) Shear
View Answer
Explanation: Burning is NOT a method used for size reduction.
5 - Question
Statement 1: Grinding laws are based on the energy required for the creation of new surface area.
Statement 2: In general, all the laws are based on the principle that the energy required per unit area of the surface is directly proportional to the size of the particle.
a) True, False
b) True, True
c) False, False
d) False, True
View Answer
Explanation: Grinding laws are based on the energy required for the creation of new surface area. In general, all the laws are based on the principle that the energy required per unit area of the surface is directly proportional to the size of the particle.
6 - Question
Statement 1: A hammer mill uses an impact to break particles.
Statement 2: A chakki uses compression to break particles.
a) True, False
b) True, True
c) False, False
d) False, True
View Answer
Explanation: A chakki uses attrition to break particles.
7 - Question
Kick’s law is an intermediate between rittinger’s law and bond’s law.
a) True
b) False
View Answer
Explanation: Bond’s law is an intermediate between rittinger’s law and kick’s law.
8 - Question
A jaw crusher uses _____
a) Compression
b) Shear
c) Cutting
d) None of the mentioned
View Answer
Explanation: A jaw crusher uses Compression.
9 - Question
A ball mill uses _____
a) Impact
b) Attrition
c) Impact & Attrition
d) None of the mentioned
View Answer
Explanation: A ball mill uses both impacts when the solids fall from the top to the bottom and attrition when the particles rub against each other and reduce in size.
10 - Question
Which of the following uses attrition?
a) Ball mill
b) Plate mill
c) Roller mill
d) All of the mentioned
View Answer
Explanation: All of the mentioned use attrition for size reduction.