Problem 1 damped free vibration, logarithmic decrement, damped free vibration, Dynamics of machinery

In a single degree damped vibrating system, a suspended mass of 8 kg makes 30 oscillations in 18 sec. The amplitude decreases to 0.25 of the initial value after 5 oscillations. Determine
1. Stiffness of the spring
2. logarithmic decrement
3. damping factor
4. damping coefficient
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