Q5/ A machine of mass 75 kg are mounted on springs and is fitted with a dashpot to damp out vibrations. There are three springs in parallel each of stiffness 10 N/mm and it is found that the amplitude of vibration diminishes from 38.4 mm to 6.4 mm in two complete oscillations. Assuming that the damping force varies as the velocity, determine (1) the resistance of the dashpot at unit velocity; (2) the ratio of the frequency of the damped vibration to the frequency of the undamped vibration; and (3) the periodic time of the damped vibration.

Q5/ A machine of mass 75 kg are mounted on springs and is fitted with a dashpot to damp out vibrations. There are three springs in parallel each of stiffness 10 N/mm and it is found that the amplitude of vibration diminishes from 38.4 mm to 6.4 mm in two complete oscillations. Assuming that the damping force varies as the velocity, determine (1) the resistance of the dashpot at unit velocity; (2) the ratio of the frequency of the damped vibration to the frequency of the undamped vibration; and (3) the periodic time of the damped vibration.

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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