Mechanical Operations If radius of a batch basket centrifuge is halved & the r.p.m. is doubled, then the Centrifugal force is doubled Linear speed of the basket is halved Capacity of centrifuge is increased Linear speed of the basket is doubled Centrifugal force is doubled Linear speed of the basket is halved Capacity of centrifuge is increased Linear speed of the basket is doubled ANSWER DOWNLOAD EXAMIANS APP
Mechanical Operations What is the critical rotation speed in revolutions per second, for a ball mill of 1.2 m diameter charged with 70 mm dia balls? 0.66 2.76 0.5 1 0.66 2.76 0.5 1 ANSWER DOWNLOAD EXAMIANS APP
Mechanical Operations As per Taggart's formula, the capacity (kg/hr) of Jaw & Gyratory crushers (for gapes of 10 to 60 cms) is equal to (where, L = Length of feed opening, cms S = Maximum width of discharge opening, cms ) √LS 250 LS 93 LS LS √LS 250 LS 93 LS LS ANSWER DOWNLOAD EXAMIANS APP
Mechanical Operations Filtrate flow rate in case of a rotary drum vacuum filter (in which Rm < < Rc) is proportional to __________ and the cycle time (where, μ = filtrate viscosity Rm = filter medium resistance Rc = cake resistance ). √μ 1/μ² 1/μ 1/√μ √μ 1/μ² 1/μ 1/√μ ANSWER DOWNLOAD EXAMIANS APP
Mechanical Operations Work index is defined as the Energy (kWh/ton of feed) needed to crush small feed to such a size that 80% of the product passes a 200 mesh screen 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 Energy needed to crush one ton of feed to 100 microns Energy needed to crush one tonne of feed to 200 microns Energy (kWh/ton of feed) needed to crush small feed to such a size that 80% of the product passes a 200 mesh screen 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 Energy needed to crush one ton of feed to 100 microns Energy needed to crush one tonne of feed to 200 microns ANSWER DOWNLOAD EXAMIANS APP
Mechanical Operations A centrifugal filtration unit operating at a rotational speed of w has inner surface of the liquid (density ρL) located at a radial distance R from the axis of rotation. The thickness of the liquid film is δ and no cake is formed. The initial pressure drop during filtration is ½w² . R . ρL(R + 2δ) ½w² . δ² . ρL ½w² . R² . ρL ½w² . δρL (2R + δ) ½w² . R . ρL(R + 2δ) ½w² . δ² . ρL ½w² . R² . ρL ½w² . δρL (2R + δ) ANSWER DOWNLOAD EXAMIANS APP