A. Surface energy created by crushing to the energy absorbed by the solid
B. Energy absorbed by the solid to that fed to the machine
C. Energy fed to the machine to the surface energy created by crushing
D. Energy absorbed by the solid to the surface energy created by crushing
Related Mcqs:
- In a size reduction crushing operation, feed size is 300 to 1500 mm while the product size is 100 to 300 mm. This is a case of the ________________ crushing?
A. Secondary
B. Fine
C. Primary
D. Ultrafine - In a size reduction crushing operation, feed size is 100 to 300 mm. while the product size is 10 to 50 mm. This is a case of the _____________ crushing?
A. Primary
B. Secondary
C. Fine
D. Ultrafine - General crushing equation is given by d(P/m) = -K (dD̅ S/D̅ n S). Bond’s crushing law is obtained by solving this equation for n = _____________ and feed of infinite size?
A. 1
B. 1.5
C. 2
D. 2.5 - In a size reduction crushing operation, the feed size is 10 to 50 mm, while the product size is 2 to 10 mm. This is a case of _______________ crushing?
A. Primary
B. Secondary
C. Fine
D. Ultrafine - What is the usual value of angle of nip for crushing of ordinary rock in smooth steel crushing rolls?
A. 16°
B. 32°
C. 40°
D. 46° - For crushing of solids, the Rittinger’s law states that the work required for crushing is proportional to __________________?
A. The new surface created
B. The size reduction ratio
C. The change in volume due to crushing
D. None of these - 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 - What is the reduction ratio in a fine crushing operation having following feed and product sizes ?
A. 0.5
B. 2
C. 5
D. 10 - According to Bond crushing law, the work required to form particle of size ‘D’ from very large feed is (where (S/V)p and (S/V)f are surface to volume ratio of the product and feed respectively) ?
A. (S/V)p
B. √(S/V)p
C. (S/V)2p
D. (S/V)f - ______________________ balls capable of grinding the feed in a ball mill gives the maximum efficiency ?
A. Cast iron
B. Minimum size
C. Maximum size
D. Elliptical
