In a system with light damping (c< cc), the period of vibration is commonly defined as...

In a system with light damping (c< cc), the period of vibration is commonly defined as the time interval τd= 2π/ωd corresponding to twosuccessive points where the displacement-time curve touches one ofthe limiting curves shown inFig. 19.11. Show thatthe interval oftime (a) between amaximum positive displacement and thefollowing maximum negative displacement is  (b) between two successive zero displacements is (c) between amaximum positive displacement and the following zero displacement is greater than