971. Filtration rate through a filter cake is proportional to (where, S = filtering surface R = specific cake resistance μ = viscosity of the filtrate) ?
A. S
B. 1/R
C. 1/μ
D. All A., B. & C.

972. The specific surface of spherical particles is given by (where D and ρ are diameter and density of particle) ?
A. 6/D.ρ
B. 2/D.ρ
C. 4/D.ρ
D. 12/D.ρ

973. Trommels are revolving screens which normally operate in the range of _______________ rpm?
A. 1 – 2
B. 15 – 20
C. 40 – 50
D. 60 – 75

974. Which of the following is not a wet classifier ?
A. Sharpies super-centrifuge
B. Hydrocyclones
C. Dorr Oliver rake classifier
D. None of these

975. Specific surface area is the surface area of a unit _______________ of materials?
A. Weight
B. Volume
C. Either A. or B.
D. Neither A. nor B.

976. Which of the following crushing laws is most accurately applicable to the fine grinding of materials ?
A. Bond’s crushing law
B. Kick’s law
C. Rittinger’s law
D. None of these

977. _______________ is a cohesive solid ?
A. Wheat
B. Sand
C. Wet clay
D. None of these

978. Moore filter is a ______________ filter ?
A. Leaf
B. Press
C. Rotary
D. Sand

979. In coal washeries, three products namely the valuable product (i.e. clean/washed coal), discarded product (i.e. mineral matter) and an additional concentrated product called _____________ is produced?
A. Concentrate
B. Tailing
C. Middling
D. None of these

980. Ordinary diffusion process is also called ______________ diffusion?
A. Pressure
B. Thermal
C. Concentration
D. Forced

NOTE
IF YOU THINK ANY OF THE MCQ ABOVE IS WRONG.
PLEASE COMMENT WITH CORRECT ANSWER AND ITS DETAIL EXPLANATION IN COMMENT BOX.
THANK YOU