A band and block brake having 12 blocks each of which subtends as angle of 20 degrees at the center is applied to a drum of 100 cm effective diameter. The drum and flywheel mounted on the same shaft weight 20 kN and have combined radius of gyration of 60 cm. The two ends of the band are attached to pins on opposite sides of the brake lever at distances of 4 cm and 16 cm from the fulcrum. If a force of 200 N is applied at. a distance of 80 cm from the fulcrum, determine (i) maximum braking torque (li) angular retardation of the drum and (iii) time taken by the system to come to rest from the rated speed of 400 r.p.m. Assume the coefficient of friction between the blocks and drum as 0.2.

A band and block brake having 12 blocks each of which subtends as angle of 20 degrees at the center is applied to a drum of 100 cm effective diameter. The drum and flywheel mounted on the same shaft weight 20 kN and have combined radius of gyration of 60 cm. The two ends of the band are attached to pins on opposite sides of the brake lever at distances of 4 cm and 16 cm from the fulcrum. If a force of 200 N is applied at. a distance of 80 cm from the fulcrum, determine (i) maximum braking torque (li) angular retardation of the drum and (iii) time taken by the system to come to rest from the rated speed of 400 r.p.m. Assume the coefficient of friction between the blocks and drum as 0.2.

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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