Aball bearing is to be selected to withstand a radial load of 7500 n and have an lto life of 5 x 108 revolutions at a speed of 2000 rpm. the bearing maker's catalog rating sheets are based on an lio life of 6000 hrs at 1000 rpm. what load should be used to size the bearing in the catalog.

Aturning operation is performed with following conditions: rake angle of 12°, a feed of 0.35 mm/rev, and a depth of cut of 1.1 mm. the work piece is aluminum alloy 6061 with t6 heat treatment (a16061-t6). the resultant chip thickness was measured to be 1.0 mm. estimate the cutting force, fc. use shear stress of 207 mpa and coefficient of friction on the tool face of 0.6.