A. D
B. 1/D
C. D2.5
D. 1/D2.5
Related Mcqs:
- Critical Speed (Nc) of a ball mill is given by (where R1 and R2 are radii of ball mill and the ball respectively) ?
A. Nc = (1/4π). √(g/R1 – R2)
B. Nc = (1/2π). √(g/R1 – R2)
C. Nc = (1/π). √(g/R1 – R2)
D. Nc = (1/2π). √(R1 – R2/g) - For achieving maximum capacity of the ball mill, the ball charge should be equal to about ______________ percent of the ball mill volume?
A. 10
B. 25
C. 50
D. 75 - In a ball mill, the volume occupied by the balls (when the mill is stopped) is about _______________ percent of the volume of the mill?
A. 35
B. 50
C. 70
D. 85 - Actual operating speed of a ball mill may vary from 65 to 80% of the critical speed. Which of the following duties would require the ball mill to be operated at maximum percentage of critical speed ?
A. Wet grinding in low viscous suspension
B. Wet grinding in high viscous suspension
C. Dry grinding of large particles (upto 1.25 cms)
D. Dry grinding of large particles in un-baffed mills - The main differentiation factor between tube mill and ball mill is the ___________________?
A. Length to diameter ratio
B. Size of the grinding media
C. Final product size
D. Operating speed - Length/diameter ratio of a ball mill is __________________ ?
A. 1.5
B. 1
C. < 1
D. > 1 - What is the critical rotation speed in revolutions per second, for a ball mill of 1.2 m diameter charged with 70 mm dia balls ?
A. 0.5
B. 1.0
C. 2.76
D. 0.66 - Which of the following gives the work required for size reduction of coal to -200 mesh in a ball mill most accurately?
A. Rittinger’s law
B. Kick’s law
C. Bond’s law
D. None of these - ______________ mill is not a revolving mill ?
A. Pebble
B. Compartment
C. Cage
D. Tube - Crushing of mineral particles is accomplished in a ‘cage mill’, when one or more alloy steel bars are revolved in opposite directions. It is a type of ______________ mill?
A. Impact
B. Roll
C. Vibratory
D. None of these
Mcq Added by: admin
