derivation of the critical speed formula of a ball mill. Pressure - Wikipedia. Pressure (symbol p or P) is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also . Inquiry Online. The Critical Speed Of A Ball Mill. question on critical speed of a ball mill,a ball mill critical speed actually ball rod ag or sag is the speed at which the centrifugal forces equal gravitational forces at the mill shells inside surface and no .derivation of critical speed of ball mill samac,critical speed of ball mill formula derivation. ball mill critical speed derivation . ball mills mine ...