Q3) Use your engineering thinking and the knowledge you got in this course to answer the following: a) Using modal analysis hammer test (free vibration): - Explain what is the pros and cons of using hammer test as compared to the shaker. - If you knock the tip of a fixed-end beam by the hammer, what natural frequencier (modes) will be excited (the 1s1, 1st \& 2nd, the first three,...or infinite number of natural froquencies? b) High 1x and 2x (sometimes 3x is also high) in the frequency domain spectrum, - is most likely a sign of (Geur wear, Misalignment or Unbulinsc)? - state what does IX mean? c) Given a mechanical iystem in a resonance case and by looking at the graph below. If you can NOT change the mass or stiffness of the model to change the natural frequcncy an - What do you nocd to do as an chgineer to avoid high resooance vibration? - Oa the graph, identity the zones for safe operation