Question

A 0.2 kg object that stretches a spring 6.5 cm
from its natural length when hanging at rest
oscillates with an amplitude of 1.5 cm.
The acceleration of gravity is 9.81 m/s2.
Find the total energy of the system.

Answer 1

The spring constant is
k = 0.2*9.81 N/0.065 m = 30.18 N/m

Total energy = (1/2) k A^2
where A is the amplitude, 0.015 m

Answer 2

120.3