Which of the following is the approximate conversion factor for sieve size to projected diameter in microscopic procedure?
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What is the maximum feed size in secondary crusher?
A. 5 cm
B. 15 cm
C. 30 cm
D. > 60 cm
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A separation dependent on optical and radioactive properties is called
A. froth floatation
B. sorting
C. gangue clearance
D. crushing
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What advantage you will get if it is known that data obtained from the material usually yields a straight line point?
A. it shows highly skewed distribution
B. burden on routine analysis would be less and relatively few sieves will be needed to check the features of size distribution
C. the linear ordinates avoids significant percentage oversize or undersize
D. this is the only numerical parameter that helps visualizing the relative frequency of occurrence of various sizes present in the material
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Which of the following bacterium is used to enhance the rate of bacterial oxidation to liberating the occluded gold for subsequent removal by cyanide leaching?
A. flocculation
B. agglomeration
C. thiobacillus ferrooxidans
D. bacillus cokki
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The path of a typical ball mill in a ball mill is
A. Circular
B. Elliptical
C. Parabolic
D. Partly circular and partly parabolic
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The radiation absorbed by elements of low atomic number is lower than that absorbed by elements of high atomic number. This variation of absorption co-efficient with atomic number can be very well applied to
A. froth floatation
B. ash determination
C. carbonization
D. agglomeration
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The mill which accepts the lowest size of feed is
A. Rod mill
B. Ball mill
C. Autogeneous mill
D. None of the above
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When the particles of same or different specific gravity come to rest at different instants, the phenomenon is termed as
A. Stratification
B. Hindered settling
C. Consolidation trickling
D. Differential acceleration
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The laser beam particle size analysis is suitably applicable for particle size measurement of
A. powdered products
B. 8 - 25 μm
C. 26 - 50 μm
D. > 50 μm
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In-situ are of 1.5% Cu got diluted with waste rock of value 0.2% Cu. If the resultant extracted ore has 1.2% Cu, what is the percentage of dilution?
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If the two particles have the same density but different diameter then which of the following is true?
A. particle with smaller diameter has the higher terminal velocity
B. particle with larger diameter has the higher terminal velocity
C. particle with smaller diameter has the lesser terminal velocity
D. particle with larger diameter has the lesser terminal velocity
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This is the method in which the particle size of the ore is progressively reduced until the clean particles of mineral can be separated?
A. crushing
B. tumbling
C. comminution
D. grinding
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Which of the following properties are utilized in froth floatation?
A. Specific gravity
B. viscosity
C. differences in physico-chemical surface properties
D. particle temperature
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Which of the following equation can be used to determine the maximum size of rock gripped in relation to roll diameter and the reduction ratio required?
A. μ k = [ ( 1 + 1.12 v ) ] ÷ ( 1 + 6 v ) μ
B. cos 2 θ = ( R + a ) ÷ ( R + r )
C. C Sin 2 θ = μ C Cos 2 θ
D. Q = B S s . cot [ a . k .60 n ] m 3 / h r
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A mineral processing plant treating almost 10,000 ton of ore per day requires water almost
A. 5 m3 /min
B. 10 m3 /min
C. 15 m3 /min
D. 20 m3 /min
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Which of the following property of frothing action is very useful in froth floatation technique?
A. frothers should not be soluble in water
B. frothers would be distributed very unevenly in an aqueous solution
C. frothers with amino group and sulpho group is preferred
D. frothers should have the ability to adsorb on the air-water interface to reducing surface tension and stabilizing air-bubble
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The general procedure for test sieving are comprehensively covered in
A. BS 1967
B. BS 1796
C. BS 1896
D. BS 2001
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Reduction ratio increases with
A. smaller size of crusher
B. larger size of crusher
C. size of ore as input
D. size is immaterial
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One of the greatest problem lies in comminution is
A. the surface area of known particles of uniform diameter is inversely proportional to the diameter
B. the probability of breakage in comminution is high for large particles and rapidly diminishes for fine sizes
C. differences exist in the breakage characteristics depending on variations in the work index
D. that most of the energy input is absorbed by the machine itself and only a fraction is available for breaking the material
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