Q 4. (a) A ball bearing subjected to a radial load of 3000 N is expected to have a satisfactory life of 10000 h at 720 rpm with a reliability of 95%. Calculate the dynamic load carrying capacity of the bearing, so that it can be selected from a manufacturer's catalogue based on 90% reliability. If there are four such bearings, each with a reliability of 95% in a system, what is the reliability of the complete system? 4. (b) A ball bearing operates on the following work cycle: Element No. Radia Spee Eleme I load (N) nt time (rрт (%) 1 3000 720 30 7000 1440 50 3 5000 900 20 The dynamic load capacity of the bearing is16.6 kN. Calculate (i) the average speed of rotation; (ii) the equivalent radial load; and (iii) the bearing life.

Q 4. (a) A ball bearing subjected to a radial load of 3000 N is expected to have a satisfactory life of 10000 h at 720 rpm with a reliability of 95%. Calculate the dynamic load carrying capacity of the bearing, so that it can be selected from a manufacturer's catalogue based on 90% reliability. If there are four such bearings, each with a reliability of 95% in a system, what is the reliability of the complete system? 4. (b) A ball bearing operates on the following work cycle: Element No. Radia Spee Eleme I load (N) nt time (rрт (%) 1 3000 720 30 7000 1440 50 3 5000 900 20 The dynamic load capacity of the bearing is16.6 kN. Calculate (i) the average speed of rotation; (ii) the equivalent radial load; and (iii) the bearing life.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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