4. (a) Self aligning bearing are being used in a head drum of conveyor. Expiain wny this selectio of self aligning bearing is important? (b) The figure below shows a solid round shaft supported by deep groove ball bearings at A and rotates B. Attached to the shaft are spurgear that are loaded as shown. The 40mm shaft 1000 rpm for 10 x 10 hours. Select suitable bearing for this condition. [8 Also select a suitable bearing if the orientation of the shaft is now changed to vertical. 100-mm dia. 50-mm dia. Dizmeter d 50 mm 4000 N 100 mm 50 mm Take following material property: Ultimate Tensile Stress (MPa) Density (kg/m Shaft 500 7850 Gear 200 7800