(a) a column with a circular cross-section and length l is subjected to a load f. (i) (ii) showing all working, develop a performance index which can be used to select a material to prevent failure which would minimise mass. show on the appropriate materials selection chart the selection line that would be used to select a material and based on this, suggest a few appropriate materials.

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.