Damping Factor Needs to be estimated experimentally Measure the ratio of two(or more)succes sive amplitudes 1 and 2, Ce 1 2 Ce-Swn(t1+Ta) Let 8=In (a1/x2). Since wd=wnV1-s V(2丌)2+6 For lightly damped systems 2丌Damping Factor Needs to be estimated experimentally: Measure the ratio of two (or more) succes￾sive amplitudes x1 and x2, x1 x2 = Ce−ζωnt1 Ce−ζωn(t1+τd) = e ζωnτd Let δ = ln(x1/x2). Since ωd = ωn q 1 − ζ 2 , ζ = δ q (2π) 2 + δ 2 For lightly damped systems, ζ ≈ δ 2π 5