Example 43 A helical spring of negligible mass and which is

Example 4.3. A helical spring, of negligible mass, and which is found to extend a 25 mm under a mass of 1.5 kg, is made to support a mass of 60 kg. The spring and the mass system is displaced vertically through 12.5 mm and released Determine the frequency of natural vibration of the system. Find also the velocity of the mass, when it is 5 mm below its rest position.

Solution

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