For the system shown in figure-3, determine:
(i) Undamped natural frequency
(ii) Damped natural frequency
(iii) Logarithmic decrement
If the mass is initially at rest, and is given a velocity of 80 mm/sec., calculate the amplitude of
vibration after 7 oscillations.
Choose k1 = (8000+20a) N/m, k2 = (7000+10a) N/m, m = 20 kg and c = (100+0.5a) N.sec/m

a=18