題組內容

1. let mass-spring-damping system with damping constant c = 2 kg/m, spring constant k =20 kg/s2, and mass is unknown:
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(1) If the mass displacement y(t) (solid line) is shown in following figure with y(0) = 1 m, y'(0)=0 m/s, please find mass m= ? kg (10%)