### AMIT 135: Lesson 7 Ball Mills & Circuits – Mining

Ball mill photographed by Ron Frisard and shared on Flickr, CC R = Mill radius; Î½ = linear mill velocity (m/s) M = Ball mass; r = ball diameter; g = gravitational acceleration ; Ball size distribution diagram [image: (135-7-11)] Critical Rotational Speed. At Î¸=0 ° and cos Î¸ = 1, the gravitational force pulling the media off the mill was maximized. Substituting and solving for