A. 3 to 4
B. 8 to 10
C. 10 to 15
D. 15 to 20
Related Mcqs:
- The capacity of a classifier in ‘tons of solid/hr’ is given by (where, A = cross-sectional area in m2, V = rising velocity of fluid in m/sec, S = percentage of solids in the suspension by volume, ρ = density of solids in kg/m3)_________________?
A. 3.6 AVS.ρ
B. 3.6 A.V.ρ
C. 3.6 A.S. ρ
D. 3.6 AVS/ρ
Answer: Option - Energy requirement (per unit mass of material crushed/ground) is highest for__________________?
A. Jaw crusher
B. Rod mill
C. Ball mill
D. Fluid energy mill - Crushing efficiency of a machine ranges between __________________ percent?
A. 0.1 to 2
B. 5 to 10
C. 20 to 25
D. 50 to 70 - Theoretical capacity of crushing rolls in tons/hr is given by (where, V = peripheral velocity, m/sec. W = width of rolls, m Dr = distance between rolls ρ = density of material to be crushed, kg/m3 here, V =πND where, N = speed of the rolls in rotation per second (rps) D = diameter of rolls, m) ?
A. 3.6 V.W.Dr.ρ
B. 3.6 V.W. ρ
C. 3.6 W.Dr.ρ
D. 3.6 V.W.Dr/ρ - The crushed material received for separation is called feed or_________________?
A. Tailing
B. Heading
C. Concentrate
D. Middling - Which of the following relationships between co-efficient of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct ?
A. μ > tan α
B. μ ≥ tan α
C. μ > tan 2α
D. μ ≤ tan α - Run of mine (ROM) coal is crushed by a _________________________ for use in domestic ovens?
A. Jaw crusher
B. Hammer crusher
C. Ball mill
D. Tube mill - The material is crushed in a gyratory crusher by the action of__________________?
A. Impact
B. Compression
C. Attrition
D. Cutting - According to Taggart’s rule for selecting between a gyratory crusher and a jaw crusher; the later should be used, if the hourly tonnage to be crushed divided by the square of the gape expressed in cm is less than_______________?
A. 0.00184
B. 0.0184
C. 0.184
D. 1.84 - Limestone is normally crushed in a _____________________?
A. Roll crusher
B. Hammer crusher
C. Ball mill
D. Tube mill
