Work index is defined as the

1.	Work index is defined as the
A.	gross energy (kWh/ton of feed) needed to reduce very large feed to such a size that 80% of the product passes through a 100 micron screen.
B.	energy needed to crush one tonne of feed to 200 microns.
C.	energy (kWh/ton of feed) needed to crush small feed to such a size that 80% of the product passes a 200 mesh screen.
D.	energy needed to crush one ton of feed to 100 microns.
Answer» B. energy needed to crush one tonne of feed to 200 microns.

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Work index is defined as the

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