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

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
by

1 Answer

Answer :

(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
by

Related questions

Work index is the gross energy (kWh/tonne of feed) necessary to reduce a very large feed to such a size that 80% of product particles will pass through a 0.1 mm screen. The value of work index determined for wet grinding should be multiplied with __________ to get the same for dry grinding. (A) 1.0 (B) 0.5 (C) 1.34 (D) 4.34

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Last Answer : (C) 1.34

Pick out the correct statement. (A) Plastic chips are called non-cohesive solids (B) Kick's crushing law is, P/m = K . ln (D̅sa /Ds̅b ) (C) Communition is a generic term for size enlargement operation (D) Energy required in kwh per ton of product, such that 80% of it passes through a 200 mesh screen, is called 'Work index'

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Last Answer : (B) Kick's crushing law is, P/m = K . ln (D̅sa /Ds̅b )

or Indian standard (IS) screens, the mesh number is equal to its aperture size expressed to the nearest deca-micron (0.01 mm). Aperture width of IS screen of mesh number 50 will be approximately __________ microns. (A) 5 (B) 50 (C) 500 (D) 5000

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Pulverised coal passing through 200 mesh screen has a diameter of 0.074 mm (74 micron). The same passing through 50 mesh screen will have a dia of __________ mm. (A) 0.007 (B) 0.30 (C) 50 (D) 0.014

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200 mesh sieve size corresponds to __________ microns. (A) 24 (B) 74 (C) 154 (D) 200

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