SIZE REDUCTION GPAT MCQs Part – 1

TOP 10 MCQ

1. Which of the following mills is based on the mechanism of impact and attrition for size reduction? [GPAT-2024]
(a) Roller mill
(b) Colloid mill
(c) Hammer mill
(d) Fluid energy mill

2. This given equation represents which law? [GPAT-2024]
E = KK  In (d1 / d2)
(a) Bond’s law
(b) Fick’s law
(c) Rittinger’s law
(d) Kick’s law

3. Rittinger’s hypothesis relates: [GPAT-2023 SHIFT-I]
[P] Energy used in size reduction
[Q] New surface area produced
[R] Equivalent shape
[S] Reynold’s number
(a) P and Q
(b) Q and S
(c) P and R
(d) P and S

4. When adhesive attractions between molecules of different species exceed cohesive attraction between like molecules, the deviation according to Raoult’s law is said to be: [GPAT-2020]
(a) Partial
(b) Positive
(c) Neutral
(d) Negative

5. Hardinge mill is a variant of: [GPAT-2019]
(a) Fluid energy mill
(b) Ball mill
(c) Hammer mill
(d) Rotary cutter mill

6. Size reduction of a material with the addition of another material is called: [GPAT-2016]
(a) Mixing
(b) Trituration
(c) Levigation
(d) Pulverization

7. A pharmaceutical API is prone to environmental oxidation. To achieve better therapeutic action, its size needs to be reduced. Method of choice for pulverization is: [GPAT-2015]
(a) Ball milling
(b) Hammer mill
(c) Colloid mill
(d) Rotary cutter mill

8. How much can be the working revolution per minute (RPM) of the ball mill? [GPAT-2013]
(a) 23–28 √D (where D = diameter of jar)
(b) Two times more than the critical revolution per minute
(c) 42.3 √D (D = diameter of jar)
(d) The average of critical RPM and the optimal RPM

9. Choose the correct combination: [GPAT-2012]
(I) Rod mill                                            (P) Dried plant drug
(II) Hammer mill                                 (Q) Thermolabile drug
(III) Fluid energy mill                         (R) Paint
(a) (I) – (Q), (II) – (P), (III) – (R)
(b) (I) – (R), (II) – (P), (III) – (Q)
(c) (I) – (Q), (II) – (R), (III) – (P)
(d) (I) – (P), (II) – (Q), (III) – (R)

10. One of the following mills works on both the principles of attrition and impact: [GATE-2002]
(a) Cutter mill
(b) Hammer mill
(c) Roller mill
(d) Fluid energy mill

ANSWER KEY