SECTION A Q1. An engine is connected to an unbalanced, rotating shaft as shown in Figure Q1. Viscoelastic shock absorbers are used to mount the engine to a frame. The engine is supported by rigid, frictionless guides that prevent it from moving in the horizontal direction. The shock absorbers can be modelled with a spring-damper system. The spring stiffness of the absorber takes on a value of k = 520 kN/m while its damping coefficient c is unknown. The entire engine-shaft assembly has a mass M of 35 kg. The equivalent mass of the shaft unbalance takes on a value of m = 1.2 kg at an offset distance r = 4 mm rotating at angular velocity w. The unbalanced rotating mass of the shaft results in a force F(t) acting in the vertical direction: F(t) = mw²r sin(wt). fremo

SECTION A Q1. An engine is connected to an unbalanced, rotating shaft as shown in Figure Q1. Viscoelastic shock absorbers are used to mount the engine to a frame. The engine is supported by rigid, frictionless guides that prevent it from moving in the horizontal direction. The shock absorbers can be modelled with a spring-damper system. The spring stiffness of the absorber takes on a value of k = 520 kN/m while its damping coefficient c is unknown. The entire engine-shaft assembly has a mass M of 35 kg. The equivalent mass of the shaft unbalance takes on a value of m = 1.2 kg at an offset distance r = 4 mm rotating at angular velocity w. The unbalanced rotating mass of the shaft results in a force F(t) acting in the vertical direction: F(t) = mw²r sin(wt). fremo

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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